Britain's Ambassador to Washington has described Donald Trump as 'inept', 'insecure' and 'incompetent' in a series of explosive memos to Downing Street.

Sir Kim Darroch, one of Britain's top diplomats, used secret cables and briefing notes to impugn Trump's character, warning London that the White House was 'uniquely dysfunctional' and that the President's career could end in 'disgrace'.

His bombshell comments risk angering the notoriously thin-skinned President and undermining the UK's 'special relationship' with America.

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Sir Kim Darroch (pictured), one of Britain's top diplomats, used secret cables and briefing notes to impugn Trump's character, warning London that the White House was 'uniquely dysfunctional' and that the President's career could end in 'disgrace'

In the memos, seen by The Mail on Sunday following an unprecedented leak, Sir Kim:

Describes bitter conflicts within Trump's White House – verified by his own sources – as 'knife fights';

Warns that Trump could have been indebted to 'dodgy Russians';

Claims the President's economic policies could wreck the world trade system;

Says the scandal-hit Presidency could 'crash and burn' and that 'we could be at the beginning of a downward spiral... that leads to disgrace and downfall';

Voices fears that Trump could still attack Iran.

In one of the most sensitive documents, Sir Kim writes: 'We don't really believe this Administration is going to become substantially more normal; less dysfunctional; less unpredictable; less faction riven; less diplomatically clumsy and inept.'

He also says that he doesn't think Trump's White House will 'ever look competent'.

In reference to Trump's ability to shrug off controversies in a life which has been 'mired in scandal', he says that the President may nonetheless 'emerge from the flames, battered but intact, like [Arnold] Schwarzenegger in the final scenes of The Terminator'.

His bombshell comments risk angering the notoriously thin-skinned President (pictured earlier this month) and undermining the UK's 'special relationship' with America

He warns senior politicians in London: 'Do not write him off.'

The leak is embarrassingly timed for the British Government, coming just weeks after the Queen welcomed Trump and his family with a 41-gun salute and a State banquet at Buckingham Palace as part of a diplomatic drive to secure a post-Brexit free-trade deal.

In a memo sent after the visit, Sir Kim warned that while Trump and his team had been 'dazzled' by the visit, and the UK might be 'flavour of the month', Trump's White House remained self-interested: 'This is still the land of America First'.

The leak is embarrassingly timed for the British Government, coming just weeks after the Queen welcomed Trump and his family with a 41-gun salute and a State banquet at Buckingham Palace (pictured) as part of a diplomatic drive to secure a post-Brexit free-trade deal

The Washington Files span the period from 2017 to the present, covering everything from Trump's policy in the Middle East to his 2020 re-election plans.

One account of a Trump rally says that there is a 'credible path' for Trump to win a second term in the White House – but describes the crowd as 'almost exclusively white'.

In what is likely to be regarded as a patronising passage in the cache, officials in London are told that in order to deal with Trump effectively 'you need to make your points simple, even blunt'.

The most incendiary paper is a letter to National Security Adviser Sir Mark Sedwill sent on June 22, 2017 – 150 days into the Trump administration – and copied to what Sir Kim describes as a 'strictly limited' number of senior figures in Downing Street and the Foreign Office.

The most incendiary paper is a letter to National Security Adviser Sir Mark Sedwill (pictured) sent on June 22, 2017 – 150 days into the Trump administration – and copied to what Sir Kim describes as a 'strictly limited' number of senior figures in Downing Street and the Foreign Office

The document, sent ahead of a National Security Council discussion on the UK-US relationship, paints a damning picture of the President's personality and leadership style.

It says media reports of 'vicious infighting and chaos' inside the White House – dismissed by Trump as 'fake news' – are 'mostly true'.

And referring to allegations of collusion between the Trump camp and Russia – since largely disproved – the memo says: 'The worst cannot be ruled out.'

One memo, sent by Sir Kim on June 22, refers to 'incoherent, chaotic' US-Iran policy, adding: 'Its unlikely that US policy on Iran is going to become more coherent any time soon. This is a divided Administration'

The cache also includes diplomatic telegrams – known as 'DipTel' in Foreign Office jargon – updating Downing Street on political events in the US and providing commentary on Trump's foreign policy decisions.

They reveal details of highly sensitive negotiations over efforts to curb Iran's nuclear weapons programme, as well as the disarray surrounding the President's handling of recent attacks on oil tankers in the Strait of Hormuz.

One memo, sent by Sir Kim on June 22, refers to 'incoherent, chaotic' US-Iran policy, adding: 'Its unlikely that US policy on Iran is going to become more coherent any time soon. This is a divided Administration'.

He questioned Trump's recent claim that he aborted a missile strike on Iran because it would have caused a predicted 150 casualties, saying it 'doesn't stand up'.

'It's more likely that he was never fully on board and that he was worried about how this apparent reversal of his 2016 campaign promises would look come 2020' – at the next Presidential election.

Another memo, sent on June 10, warns of tensions ahead over Brexit: 'As we advance our agenda of deepening and strengthening trading arrangements, divergences of approach on climate change, media freedoms and the death penalty may come to the fore.'

The leak of diplomatic cables is extremely unusual and will raise new questions about morale in the Civil Service.

When dealing with Trump you need to make your points simple, even blunt

There is mounting evidence that Brexit has politicised many mandarins, with officials who privately support Brexit accusing the Civil Service of trying to stop the UK leaving the EU.

Darroch, who became British Ambassador to Washington in January 2016, is a former UK Permanent Representative to the EU and widely regarded as a europhile.

The Foreign Office last night said that the British public 'would expect our Ambassadors to provide Ministers with an honest, unvarnished assessment of the politics in their countries'.

A spokesman added: 'Their views are not necessarily the views of Ministers or indeed the Government. But we pay them to be candid, just as the US Ambassador here will send back his reading of Westminster politics and personalities.

'Of course we would expect such advice to be handled by Ministers and civil servants in the right way and it's important that our Ambassadors can offer their advice and for it remain confidential.

'Our team in Washington have strong relations with the White House and no doubt that these will withstand such mischievous behaviour.'

Trump's speeches are 'full of false claims' and the White House 'will never look competent': Ambassador's withering views reveal scale of concern British Government has about President

It was summer 2017, and Britain's National Security Council was convening to discuss a problem. President Trump had been in office for 150 days, and Prime Minister Theresa May and her Cabinet colleagues were still struggling to get a handle on his chaotic Administration. They needed advice.

At his desk in his splendid official residence in Washington DC, the British Ambassador, Sir Kim Darroch was trying to help. Britain's National Security Adviser Sir Mark Sedwill had asked him to put together some thoughts on the President's personality and leadership style, and he was compiling a briefing note.

Copied to a 'strictly limited' number of senior figures in Downing Street and the Foreign Office, it ran to six pages of highly unflattering observations about the President's character and political record.

In the confidential memo – marked 'Official Sensitive' – the UK's most important diplomat accused Trump of 'radiating insecurity', filling his speeches with 'false claims and invented statistics' and achieving 'almost nothing' in terms of domestic policy.

Earlier, Sedwill had sent Sir Kim an outline presentation for the meeting. Sir Kim thought the slides 'looked good'. There was just one point he felt he needed to correct: 'My only disagreement with the slides: I don't think this Administration will ever look competent,' he declared.

It was an extraordinarily damning assessment. The problem was that Ministers and diplomats had to find a way to deal with the President.

Sir Kim highlighted how America was still the UK's No 1 security partner and the 'cultural and historical ties' between the two countries were 'profound'. The UK needed America: as an export market; for defence and intelligence cooperation; and for a post-Brexit trade deal.

'The starting point is that this is our single most important bilateral relationship,' Sir Kim wrote.

But he added: 'As seen from here, we really don't believe that this Administration is going to become substantially more normal; less dysfunctional, less unpredictable, less faction-riven, less diplomatically clumsy and inept.'

There's no upside in being subtle, let alone being ambiguous

He therefore compiled a three-point guide for how Britain's politicians and officials should handle this most unpredictable of Presidents. His first suggestion was to 'flood the zone', which meant influencing as many of the President's key advisers as possible.

Sir Kim said Trump spends his days in the Oval Office asking his White House team, Cabinet members and senior Republicans for their opinions 'on the business of the moment'.

But, crucially, the diplomat also highlighted how the President spends his evenings phoning his friends outside the administration 'seeking reinforcement or a different take'. Many of these friends have been 'cultivated' by the British, Sir Kim boasted.

'It's important to 'flood the zone': you want as many as possible of those who Trump consults to give him the same answer,' he wrote. 'So we need to be creative in using all the channels available to us through our relationships with his Cabinet, the White House staff, and our contacts among his outside friends.'

Sir Kim's second recommendation was for Theresa May to call Trump more often, stressing 'there is no consistently reliable substitute for the personal phone call from the Prime Minister'.

Sir Kim said Trump spends his days in the Oval Office asking his White House team, Cabinet members and senior Republicans for their opinions 'on the business of the moment'

'The President respects and likes her,' he added. 'I know they have already talked several times. But in a perfect world, they would be speaking two or three times a month, if not more.'

The diplomat's third pointer was to urge Britain's politicians and officials to use flattery and to pander to the President's ego when they come into contact with him.

'You need to start praising him for something that he's done recently,' he advised. 'You need whenever possible to present them as wins for him.' In comments which could be viewed as highly patronising, Sir Kim also advised his bosses to make their points 'simple' and 'even blunt', adding: 'as a senior White House adviser told me, there is no upside with this President in being subtle, let alone ambiguous.'

His stark assessment reveals the scale of concern at the highest level in the British Government about Trump. By summer 2017, the President had torn up the Paris climate change accord; junked key international trade agreements and launched military strikes against Syria. Western allies were reeling: he didn't seem to care who he upset.

You need to start by praising him for something he's done recently

But while Trump was making waves on the world stage, his domestic programme was getting nowhere, Sir Kim said.

The President's big election pledges – building a wall between the US and Mexico; stopping Muslims from certain countries coming to America and reforming tax and healthcare – had all hit the buffers.

'Of the main campaign promises, not an inch of the Wall has been built; the executive orders on travel bans from Muslim countries have been blocked by the state courts; tax reform and the infrastructure package have been pushed into the middle distance; and the repeal and replacement of Obamacare is on a knife edge,' Sir Kim wrote. The Ambassador 'wouldn't bet a tenner' on Trump's health proposals passing through the Senate.

Sir Kim's confidential letter, sent to Sedwill, who is now also the Cabinet Secretary, on June 22, 2017, is unsparing in its assessment of the President's personality flaws and the chaos of his administration.

In language that is likely to prove highly embarrassing for Sir Kim, the Ambassador declared: 'For a man who has risen to the highest office on the planet, President Trump radiates insecurity.'

He highlighted how the Administration had been 'dogged from day one by stories of vicious infighting and chaos inside the White House, and swamped by scandals – all, one way or another, linked to Russia.'

And while the President would deride media stories about such chaos as 'fake news', Sir Kim privately advised his bosses in London to believe what they were reading in the newspapers. 'The stories about White House knife fights are, we judge, mostly true: multiple sources and confirmed by our own White House contacts. This is a uniquely dysfunctional environment.' He warned Whitehall to be braced for more presidential outbursts including the use of 'immoderate, sometimes offensive, language', like his attacks on London Mayor Sadiq Khan.

'There is no filter,' Darroch advised. 'And we could also be at the beginning of a downward spiral, rather than just a rollercoaster: something could emerge that leads to disgrace and downfall.'

But while warning Whitehall that Trump's White House could collapse under the weight of scandal, he also urged the British Government not to write Trump off.

The President, he noted, has been mired in scandal most of his life but has always survived.

Sir Kim drew a parallel with The Terminator, a 1984 science fiction film featuring Arnold Schwarzenegger as a cyborg that is almost impossible to destroy.

'Trump may emerge from the flames, battered but intact, like Schwarzenegger in the final scenes of The Terminator.'

Looking to the future, Sir Kim warned 'there are real risks on the horizon' and that Trump 'will do or say things we oppose'.

'This 'America First' Administration could do some profoundly damaging things to the world trade system: such as denounce the WTO, tear up existing trade details, launch protectionist action, even against allies. It could further undermine international action on climate change, or further cut UN funding.' He said that Trump's 'spontaneous' missile strike on a Syrian airbase in April 2017 had won him 'the best headlines of his brief time in the Oval Office' but warned that 'a less well judged military intervention is not inconceivable.'

In the face of the chaos, Sir Kim highlighted how German Chancellor Angela Merkel, and French President Emmanuel Macron, were busy distancing themselves from Trump. But Sir Kim warned London: 'I don't think we should follow them.'

He admitted it could be rocky, but suggested that sometimes it might make sense to criticise the President, 'provided we are careful'. Sir Kim added: 'Arguably, you get more respect from this President if you stand up to him occasionally – provided the public comments do not come as a surprise and are judicious, calm and avoid personalising.'

Today he may regret that his confidential memo does not meet that test.

Indeed, last night, Brexit Party leader Nigel Farage, a friend of the President, called for Sir Kim to leave his post, saying: 'The sooner he is gone the better.'

The council house kid who ended up with a plum job: How Sir Kim Darroch secured a prestige position by winning scholarship to £20,000 private school before taking Foreign Office role because 'they were the first to offer him work'

Sir Kim Darroch's gilded lifestyle, meeting the great and the good at Britain's lavish Ambassador's residence in Washington DC, is a world away from the council flat he grew up in.

His parents split up when he was just six years old, forcing his family to leave behind their hitherto comfortable life in Nairobi, Kenya, where his father taught in a private school.

His mother Edna moved Kim and his younger brother back to Britain and into a flat on a council estate in Abingdon, Oxfordshire.

From there, many boys would have gone on to work in manual employment. But Kim, a bright student, had other ideas.

After soaring through the entrance exams, he won a free scholarship to attend Abingdon School, a leading public school that charges £20,000 a year for day pupils.

After soaring through the entrance exams, he won a free scholarship to attend Abingdon School (pictured), a leading public school that charges £20,000 a year for day pupils

'I think I was the only person in the school uniform walking out of this council estate every morning to go to school,' he recalled in a recent interview.

'I think what it teaches you is that all things are possible no matter where you come from, if you put the work in.'

After finishing his A-levels, he studied zoology at Durham University because – in his own words – he was 'naturally lazy' and it was an 'easier option'.

He joined the Foreign Office in 1977 after graduating because 'they were the first people to offer me a job' and started his ascent through the ranks at Embassies around the world, including top roles dealing with EU bureaucrats in Brussels.

When he landed the most prestigious diplomatic post in the Foreign Office – British Ambassador to the United States – in 2016, Barack Obama was winding down his presidency. Sir Kim and his wife Vanessa, who he married in 1978, soon settled into the comfortable private apartment in the Embassy, widely regarded as the finest in Washington DC.

It has a ballroom, boutique hotel-style guest rooms, a library and beautiful gardens. It was his reward for 40 years in the Civil Service, and he threw himself into the social whirl. The residence hosts almost 800 breakfasts, lunches, dinners and cocktail parties a year, and Sir Kim reportedly shows up at 90 per cent of them.

His job was relatively straightforward – until Donald Trump arrived.

Days after winning the Presidential election in November 2016, Trump was tweeting that he'd prefer his friend Nigel Farage, the former Ukip leader, to be Britain's Ambassador to the US.

Days after winning the Presidential election in November 2016, Trump was tweeting that he'd prefer his friend Nigel Farage (pictured with Trump in August 2016), the former Ukip leader, to be Britain's Ambassador to the US

No 10 insisted it was for Britain to decide who serves as its Ambassador, while Sir Kim bit his tongue. But it's clear Trump created unprecedented challenges even for this most experienced of diplomats.

There is no doubting Sir Kim's deep patriotism (his mobile phone cover is a Union Jack) and colleagues in the Foreign Office consider him to be a first rate diplomat. However, it is his long postings in Brussels that have earned him a reputation as a europhile, and he is mistrusted by Brexiteers.

He was Tony Blair's top Europe adviser from 2004 to 2007 and then became Britain's Permanent Representative to the EU from 2007 and 2011.

Knighted in 2008, he became David Cameron's National Security Advisor, from January 2012 to September 2015, before his Washington posting.

Now aged 65, Darroch is nearing the end of his diplomatic career.

Even before today's revelations in The Mail on Sunday, few expected him to survive in Washington DC after the next UK Prime Minister takes office.

Now these unfortunate leaks may just hasten his departure.

But Ambassador STILL says The Donald can win again!

Donald Trump could win a second term in the White House, Sir Kim Darroch told Downing Street, saying there is a 'credible path' for him to sweep to victory in next year's Presidential election.

In a leaked diplomatic cable sent on June 20, the Ambassador reported how two days earlier the President had 'electrified' an audience of 20,000 supporters in Orlando, Florida, at a huge rally to launch his re-election campaign.

A senior British diplomat was in the Amway Center, an indoor sports stadium, to witness the event and report back to Sir Kim.

In a leaked diplomatic cable sent on June 20, the Ambassador reported how two days earlier the President had 'electrified' an audience of 20,000 supporters in Orlando, Florida, at a huge rally to launch his re-election campaign (pictured)

The Ambassador told London that while the President had not offered any new policies, 'the crowd could not have been happier'.

'The atmosphere was unique – somewhere between a major sporting event (where only the home team fans are in the crowd) and a mega-church. Indeed the event kicked off with prayers from a pastor who asked God to 'tear down' opposition to the President.'

Sir Kim said the audience was a 'sea of the now iconic red MAGA [Make American Great Again] caps. The crowd looked almost exclusively white, with a pretty even mix of men and women, young and old: there were families in every stand. For some, attending had meant a long wait in 30C heat and humidity.'

Sir Kim said the audience was a 'sea of the now iconic red MAGA [Make American Great Again] caps. The crowd looked almost exclusively white, with a pretty even mix of men and women, young and old: there were families in every stand. For some, attending had meant a long wait in 30C heat and humidity'

Sir Kim predicted that the President's campaign strategy will be to 'go with what he knows best' and appeal to his core supporters.

He noted how the enthusiasm of his 'die-hard fans' is undiminished after two-and-a-half years in the Oval Office. In comments that could anger the White House, Sir Kim reported that: 'As is standard at these rallies, the language was incendiary, and a mix of fact and fiction – hard to reconcile with [Vice President Mike] Pence's remarks about governing for all Americans.'

A key difference between when Trump last ran for President in 2016 is that the machinery of the Republican Party is 'four-square behind him', Sir Kim said.

Sir Kim said the President still faces hurdles – including the prospect of the Democrats picking a candidate more popular than the widely disliked Hillary Clinton, who fought the last election.

He also said Trump cannot afford to lose much support and stressed that the President has made no meaningful efforts to 'diversify his base'.

'All that said, there is still a credible path for Trump – but so much rides on who the Democrats choose in July 2020.'

How Trump told British Ambassador the special relationship felt 'closer and stronger' after state visit but warned 'don't expect any special favours'

As the President and First Lady boarded Air Force One at Southampton, Sir Kim Darroch breathed a sigh of relief. Their State visit to the UK was finally over and, despite minor hiccups, it had been a resounding success.

Moments earlier, on the Tarmac, Donald Trump had taken his leave of the various UK Government officials and dignitaries who had gathered to see him off.

The formalities – six months in the planning – were now over. All that remained was for Sir Kim, who had accompanied the President throughout the three-day trip, to bid him farewell. 'This was a wonderful visit, and UK-US relations are now in the best state ever,' Trump told him, shaking his hand.

As the President and First Lady boarded Air Force One at Southampton, Sir Kim Darroch breathed a sigh of relief. Their State visit to the UK (pictured with the Queen in Buckingham Palace for the State Banquet) was finally over and, despite minor hiccups, it had been a resounding success

The British Ambassador to Washington could hardly hide his delight.

Somehow he had managed to pull off what had, at times, looked an almost impossible feat: showing America's First Family the very best of British pomp and circumstance and steering him through multiple potentially tricky meetings and engagements, without any unwelcome drama. It was the pinnacle of his 40-year career in the Civil Service.

Iran: His missile attack u-turn claim 'doesn't stand up' American policy towards Iran is incoherent and unlikely to improve 'any time soon', according to a devastating memo by Sir Kim Darroch. In a damning indictment of Donald Trump's administration, Britain's Ambassador to Washington described '36 hours of contradictory messaging and decisions' after Iran shot down a US military drone last month. The missile strike by Iran's Islamic Revolutionary Guard took America to the brink of launching a retaliatory attack. But after authorising a strike and boasting of being 'cocked and loaded', President Trump aborted the mission with ten minutes to spare after being told that it might kill as many as 150 people. Blame: The US says Iran attacked this oil tanker in the Gulf of Oman in June Tensions have been escalating between the US and Iran since May 2018, when Trump announced the US was withdrawing from a nuclear agreement with Iran and was reimposing sanctions on the regime. The US has blamed Iran for a series of recent attacks on oil tankers in the Gulf of Oman. In his memo, written at 12.39am UK time on June 22, Sir Kim described disarray and confusion across Washington as Trump unexpectedly aborted the attack. 'The Administration said nothing for several hours, awaiting guidance from the White House,' he wrote. 'Even our best contacts were unwilling to take our calls.' Sir Kim said the episode illustrated Trump's 'aversion to new military adventures'. But, astonishingly, he made it clear to London that he did not believe the President's explanation of why he cancelled the attack. 'His claim, however, that he changed his mind because of 150 predicted casualties doesn't stand up; he would certainly have heard this figure in his initial briefing. 'It's more likely that he was never fully on board and that he was worried about how this apparent reversal of his 2016 campaign promises would look come 2020 [at the next election].' He warned that this is a 'divided Administration' and that 'it's unlikely that US policy on Iran is going to become more coherent anytime soon'. And while Trump had stepped back from the brink this time, Sir Kim warned that the President could still trigger a conflict with Iran, noting that he is now 'surrounded by a more hawkish group of advisers'. 'This may, however, only be a temporary pause,' he warned. 'Just one more Iranian attack somewhere in the region could trigger yet another Trump U-turn. Moreover, the loss of a single American life would probably make a critical difference.' Advertisement

Back at his desk in Washington, almost two weeks later, Sir Kim was still buzzing. He settled down to write a long memo to Prime Minister Theresa May and other senior Government figures reflecting on what had been achieved.

'We are basking in a big success, with doors open everywhere in Washington,' he gushed in a diplomatic cable sent last month and marked 'Official Sensitive'. 'As a result, our relationship with this Administration, at this critical juncture for the UK, feels closer and stronger.'

But he warned London not to get too carried away, stressing that this was 'still an Administration of 'no special favours'.'

'We might be flavour of the month, but this is still the land of 'America First',' he concluded.

Sir Kim could be forgiven for feeling pleased with himself. The smooth running of what was only the third State visit of a US President to the UK (the others were George W Bush and Barack Obama) had been by no means assured.

Indeed, the President had barely entered UK airspace before there were signs of trouble.

Moments before touching down in London, he had fired off a characteristically aggressive tweet about the city's mayor Sadiq Khan, labelling the Labour politician a 'stone cold loser' and making a disparaging comment about his height.

It was hardly the diplomatic start Sir Kim had hoped for. If the President continued to behave like this, the visit would be a disaster.

For all the President's bombast, Sir Kim knew he was nervous. He was excited about seeing the Queen again – they had met for the first time almost exactly a year earlier – but had been fretting about messing up.

Last time, he had been accused of various gaffes, and he was 'worried about getting the protocol right', Sir Kim later reported.

The Ambassador knew that Her Majesty would take any minor slips in her stride. He was much more concerned about the President meeting Prince Charles.

The President and the heir to the throne did not see eye-to-eye over the environment. What if they had some embarrassing row?

Then there was the diplomatic minefield posed by the looming Tory Party leadership contest. Mrs May was on her way out, and the President would have to decide which of the dozen or so MPs vying for her job he should take time to meet. What if he backed the wrong horse?

Furthermore, there were difficult discussions looming over Chinese telecoms giant Huawei. The President was annoyed by the UK's refusal to cut ties with the company. It could be awkward.

Greatly to Sir Kim's relief, however, everything went to plan.

From his splendid official residence on Massachusetts Avenue in Washington DC – once described as 'Downton Abbey on the Potomac' – Sir Kim reflected on what had been achieved.

He penned a long diplomatic telegram on June 17 on the 'impressions and implications' of the State visit. The memo was sent at 2.15am, UK time, guaranteeing that it would be read at the beginning of the working day in London.

'With this unorthodox President, there were genuine risks… In the event, the gamble paid [off] handsomely,' he wrote in the cable that was sent to No 10 and senior officials across Whitehall.

Though Trump was now 'used to being feted by foreign governments,' the State visit was 'an honour that no other country can match' and Trump had 'revelled in every element of it'.

'The President knew from the outset that it amounted to genuinely special treatment…. Although initially worried about getting the protocol right, he became more relaxed as it progressed; and by the end, he could not have been happier or more fulsome in his assessment,' Sir Kim wrote in the telegram.

According to the Ambassador, the highlight for the President had been the 'extensive personal engagement' with the Queen: at a private lunch, at a glittering State banquet, and at the D-Day commemorations in Portsmouth.

Cordial: Trump hit it off with Charles - surprisingly. Trump 'seemed to deeply appreciate' the effort the Prince of Wales and the Duchess of Cornwall made. 'I think the Prince of Wales, despite differing views on climate change, established an open and easy relationship with the President,' he wrote

However, he had also got on surprisingly well with Charles and Camilla. Trump 'seemed to deeply appreciate' the effort the Prince of Wales and the Duchess of Cornwall made. 'I think the Prince of Wales, despite differing views on climate change, established an open and easy relationship with the President,' he wrote.

Throughout the visit, Sir Kim had also been conscious of the need to keep Trump's aides happy. The President had travelled with a huge entourage, all of whom needed to be looked after. That had gone equally well.

'His team were also dazzled, telling us that this had been a visit like no other – the hottest ticket of their careers,' he reported.

Russia: The presidency could crash and burn over Russia links Donald Trump's alleged links to Russia could see his presidency 'crashing and burning', Ambassador Darroch said in one memo. In a controversial briefing note written two years ago, Sir Kim Darroch warned his bosses in London that of all the President's troubles, allegations of collusion between the Trump camp and Russia – since largely disproved – had the greatest potential to finish him. At the time, evidence was mounting that his campaign team had conspired with Vladimir Putin's regime to beat Hillary Clinton in the 2016 presidential election. There were also unproven claims his son-in-law Jared Kushner may have been indebted to shady Russian moneymen. The British Ambassador feared they might be true. 'The worst cannot be ruled out,' he said, in a letter written for the UK's National Security Adviser Sir Mark Sedwill in June 2017 marked 'Official Sensitive'. 'There could have been active collusion between individuals associated with the Trump campaign and Russian intelligence, especially over the timing of release of hacked emails from inside the Clinton camp. Dodgy Russian financiers may have bailed out the Trump and Kushner enterprises when both were at risk of bankruptcy in previous decades,' he declared. A month earlier, in May 2017, Special Prosecutor Robert Mueller had launched an investigation. Trump was accused of trying to stop a probe into his former National Security Adviser Michael Flynn. Once again, Sir Kim was uneasy. 'Trump's attempts to close down the FBI investigation... might amount to obstruction of justice,' he said. This would be a criminal offence. He warned Sedwill that Trump could win a second term, but 'we can't rule out his crashing and burning either'. For all his misgivings, Sir Kim also told Sedwill he 'wouldn't bet' on any of it bringing the President down. 'Trump has been mired in scandal pretty much all his life, and has come through it. He seems indestructible,' he wrote. Advertisement

Impressing Trump's advisers was far more than a matter of manners.

Cultivating contacts in the White House and Trump administration was a key part of Sir Kim's job. He liked to call those with the President's ear the 'Trump Whisperers.' Now he was on even better terms with them.

'These are close contacts, with whom we have spent years building relationships: they are the gatekeepers... the individuals we rely upon to ensure the UK voice is heard in the West Wing.

'The visit will make a substantial difference to those relationships too,' he enthused.

On their return to the US, Sir Kim and his team had 'done the rounds with journalists, pundits and commentators'. Media coverage had been great.

'With some nuances, their view was that we had pulled off a difficult task: a largely gaffe-free visit which had made a President who often stumbled on foreign trips look good, and which had shown the UK, at a difficult juncture, at its best,' Sir Kim declared.

Mercifully little had been made of 'potentially controversial moments' like public protests, the spat with Khan, and 'private meetings with some prominent UK politicians', including Nigel Farage.

Instead, American journalists had focused on 'how much the President appeared to be enjoying himself; how relaxed a relationship he appeared to have developed with the Queen; and how well the talks and lunch with the Prime Minister appear to have gone', Sir Kim wrote.

Now it was a question of capitalising on these gains. The Ambassador told his bosses back home that he would be building on the 'enhanced personal relationship with the Trump inner circle to deliver UK objectives'. Thinking ahead, he felt that the State visit could be used to lay the ground for Theresa May's successor – Boris Johnson or Jeremy Hunt – to secure an early meeting with the President.

The new Prime Minister would be 'starting in the best possible place with this President', he said.

He suggested a possible early meeting at the UN General Assembly in New York in mid-September ('though Brexit considerations may intrude here') or 'in the margins of the Nato summit in December'.

But the new Prime Minister could also make a formal visit to the White House.

'I am sure that there would be a warm welcome here in Washington if that's what we want to happen,' Sir Kim said.

But perhaps conscious that his report might sound too self-congratulatory, Sir Kim signed off with a warning that despite the successful visit, America would not cut the UK any slack in trade negotiations and would continue to press the UK to 'choose between them and China'.

They would measure the UK by 'what resources we bring to the table', he cautioned.