The Mail on Sunday today reveals startling new evidence of long-standing links between Jeremy Corbyn’s closest adviser and Middle Eastern terrorist groups, together with an outspoken defence of Russian interests dating back decades.

Our investigation shows that Seumas Milne, the Labour Party’s strategy and communications chief – a man described by some insiders as ‘Corbyn’s brain’, such is his influence – has for decades expressed support for militant groups openly dedicated to destroying Israel by force.

The revelations will heap further pressure on a Labour leader mired in accusations of institutional anti-Semitism, and reeling from the resignation of nine of his MPs, most of whom cited racist abuse of Jewish MPs by Corbyn supporters as a reason for their departure.

Our investigation shows that Seumas Milne, the Labour Party’s strategy and communications chief – a man described by some insiders as ‘Corbyn’s brain’, such is his influence – has for decades expressed support for militant groups openly dedicated to destroying Israel by force

One prominent Jewish Labour MP, who wished to remain anonymous for fear of ‘death threats’ by Corbyn loyalists, told The Mail on Sunday: ‘I think it’s evident to anyone who has been in the Parliamentary Labour Party for the past three years that Seumas Milne has an undue influence on events. It’s not just concerning – it’s appalling, especially over the issue of anti-Semitism.’

Our investigation also shows that Milne has parroted Kremlin propaganda, defending Russian aggression against its neighbours, from its invasion of Afghanistan in 1979 to Vladimir Putin’s ongoing campaign against Ukraine. Our findings prompted the former head of MI6 to warn last night that if Corbyn were to win a General Election, he would have to cut off contact with Milne because of the risk Milne poses to national security.

Sir Richard Dearlove, who led the Secret Intelligence Service between 1999 and 2004, said Milne stood ‘no chance’ of passing Whitehall’s system of background checks, known as developed vetting, and so could not be allowed to see classified documents.

The Mail on Sunday can reveal:

During a university vacation in 1977, Milne visited Lebanon during its civil war, and met Palestine Liberation Organisation (PLO) terrorists dedicated to destroying Israel by violence;

Returning to England, he set up and ran a campaign to spread PLO propaganda at Oxford University;

Later, Milne forged links with Hamas, which remains committed to Israel’s destruction and has perpetrated hundreds of terrorist attacks – and travelled with Corbyn to meet its leaders on a trip to the Middle East funded by UK Hamas sympathisers in 2010;

After graduating in 1979, he became the business manager for a hardline, pro-Soviet newspaper that backed PLO violence, Ayatollah Khomeini’s Islamic revolution in Iran, the taking of American hostages and the Russian invasion of Afghanistan;

The paper’s star columnist was a long-standing Kremlin mole;

Milne personally backed the 1979 Soviet invasion of Afghanistan, the trigger for decades of terrorist violence, arguing that it was a ‘progressive’ event that was ‘liberating’ Afghan women and improving human rights;

As a reporter for The Guardian newspaper in the 1980s, Milne acquired a powerful mentor – features editor Richard Gott, who was later forced to resign after admitting that he took a series of foreign trips paid for by the Soviets, during which he met KGB officials;

After the 1984 Provisional IRA bombing of the Grand Hotel in Brighton during the Tory Party conference – which killed five people and injured 31 – Milne told Guardian colleagues ‘I think it is a very daring attack’, as maimed victims were still being carried from the wreckage;

In 2014 he chaired a conference session in Russia at which the star speaker was Vladimir Putin, with all his expenses paid for by its organisers, a think-tank close to Putin’s government. Afterwards, he was criticised by his colleagues at The Guardian, which had boycotted the event because it took place just months after Russia illegally seized Crimea from Ukraine.

Last summer, when the depth of Labour’s anti-Semitism crisis first became apparent, Jeremy Corbyn tried to stop Labour adopting the full and unmodified International Holocaust Remembrance Alliance (IHRA) definition of anti-Semitism.

The IHRA says it is anti-Semitic to claim the State of Israel is an inherently ‘racist endeavour’ which has no right to exist. Milne has supported groups that make this anti-Semitic claim and advocate violence to achieve their goals since he was a teenager. Moderate Labour MPs say Milne’s beliefs have an ‘undue influence’ on Labour policy and its mishandling of the anti-Semitism crisis that has engulfed the party.

Last summer, when the depth of Labour’s anti-Semitism crisis first became apparent, Jeremy Corbyn tried to stop Labour adopting the full and unmodified International Holocaust Remembrance Alliance (IHRA) definition of anti-Semitism

They claim the 60-year-old wields power over the party leader which is unprecedented for someone in his position as spin doctor.

‘Again and again, MPs have asked to see Corbyn to talk about anti-Semitism, and when they got to his room, they found themselves talking to Milne,’ one MP said.

The MP added: ‘The only reason I am reluctant to put my name to this is that I know that, if I do, I will get death threats. But he has absolute, complete influence over Corbyn. I don’t think Jeremy makes a decision about anything without Seumas Milne signing off on it.’

A senior party staff member said: ‘Without a shadow of a doubt, Corbyn trusts Milne more than anyone. I actually think Corbyn is a little bit thick. It’s no exaggeration to say that Milne is Corbyn’s brain.’

He added that this was why Corbyn resisted the full IHRA definition of anti-Semitism until he was finally overruled by his National Executive: ‘Seumas has been supporting groups that deny Israel’s right to exist for many years.’

Milne forged links with Hamas, which remains committed to Israel’s destruction and has perpetrated hundreds of terrorist attacks – and travelled with Corbyn to meet its leaders on a trip to the Middle East funded by UK Hamas sympathisers in 2010

Last week, this newspaper published extracts from Tom Bower’s explosive biography of Corbyn that documented a meeting between the president of the Board of Deputies of British Jews and the Labour leadership that was marked by ‘flippant disdain’ on the part of Milne and the Labour leadership.

Corbyn’s tendency to defer to Milne – especially over Israel and anti-Semitism – was clearly evident when he gave previously unreported evidence to an inquiry on anti-Semitism by the Commons Select Committee on Home Affairs in 2016.

Asked about Milne’s expressions of support for Hamas, an organisation that believes Israel must be destroyed through ‘armed resistance’, Corbyn refused to criticise him, saying: ‘I don’t think it is appropriate for me to be quizzed on his individual views. He is a man of immense intellect and a scholar.’

This newspaper has spoken to several sources who knew Milne at Oxford, where he read Politics, Philosophy and Economics from 1976 at Balliol College. All say that while a student, he spent months in the Middle East, part of the time in Lebanon, the site of Palestinian refugee camps controlled by the PLO, which was then dedicated to ‘the liberation of Palestine through armed struggle’.

The country was in the throes of a vicious civil war, so it was an unusual destination for a public schoolboy, whose father, Alasdair, would soon be appointed Director-General of the BBC.

A profile of Milne in the Left-wing New Statesman magazine stated that in Lebanon ‘he learned Arabic, heard shots fired in anger, escaped from a blown-up building and was briefly captured by militiamen’. Claims he attended a terrorist training camp there – which surfaced several years ago in political blogs – were, the article said, dismissed by Milne’s former colleagues at The Guardian as ‘ludicrous’, and yesterday a Labour spokesman said the claim was ‘entirely false’.

So what was he doing? Palestinian writer and political activist Hussein Agha knew Milne at Oxford and still knows him now. He told the MoS: ‘I met him when he came back. He was not anti-Semitic, but he was very, very anti-Israel.

‘He went to Lebanon, Syria and the West Bank – a young boy on a Leftist grand tour. He adopted a Palestinian accent. He used to speak English with Arabs the way they spoke to him.’

Mr Agha said that Milne met with members of Fatah, the PLO’s dominant group led by the late Yasser Arafat – its constitution declared that defeating the ‘Zionist invasion’ was an ‘Arab religious and human obligation’. A Labour source insisted: ‘Seumas has never advocated violence. The right to resist illegal occupation is enshrined in international law.’

At Oxford, with help from Mr Agha, Milne co-founded the Oxford Palestine Campaign.

Shortly afterwards, Alasdair Milne had lunch with the Oxford philosopher Sir Isaiah Berlin. He boasted, Sir Isaiah recorded afterwards, that young Seumas had become ‘the Oxford representative of the Friends of the PLO’.

The campaign’s founding leaflet, issued on November 11, 1977, stated: ‘We sell literature produced by a wide range of organisations who support the legitimate rights of the Palestinian people, from various groups that make up the PLO to progressive anti-Zionist groups operating in this country.’

The campaign argued there could ‘be no peace or justice’ in the region following ‘the establishment and perpetuation of an exclusively Jewish state where the majority of the population were non-Jews, as the Zionists like to refer to the Palestinians’.

In September 1978, when Israel and Egypt signed a peace treaty brokered by US President Jimmy Carter, Milne’s Oxford Palestine Campaign issued a scathing condemnation, describing it as a ‘sordid little deal’ cooked up to safeguard the West’s supply of oil. It added: ‘We must now expect the Palestinians to react in the only way that is left to them: to escalate their armed resistance.’

According to Mr Agha, Milne’s views have stayed the same for decades, although his own had shifted and he played a key role in peace negotiations. He commented: ‘He thinks I have sold out, become too soft. He is a purist.’

Indeed, in 2009, Milne wrote that ‘the idea that Israel is a racist state is largely uncontroversial’, saying it was ‘built on ethnic cleansing’. In 2012, he wrote that Hamas had ‘regained credibility as a resistance force’, and noted with apparent approval that rockets fired from Gaza now had the range to hit targets in Jerusalem or Tel Aviv.

As well as meeting Hamas leaders with Corbyn in 2010, Milne has spent time with them at conferences organised by the Al Jazeera TV station in Qatar.

Besides sponsoring suicide bombings and rocket attacks from its stronghold in Gaza, Hamas describes Israel as ‘the Zionist enemy’, and says there is no alternative ‘to the full and complete liberation of Palestine, from the [Jordan] river to the sea’.

It also defends violence as the means to accomplish this, saying armed ‘resistance’ is a ‘legitimate right guaranteed by divine laws’. A Labour source said: ‘Seumas Milne does not endorse the Hamas charter. He has criticised it.’

AFTER leaving Oxford in 1979, Milne became business manager for a hard-Left newspaper, Straight Left. Run by ‘Stalinist’ members of the Communist Party and a handful of Labour MPs, it was set up to counter the ‘reformist’ soft Left, which was influencing both Labour and the Communists.

Straight Left’s articles from this period, unearthed by the MoS from the vaults of the British Library, make eye-watering reading.

For example, numerous articles hailed Ayatollah Khomeini’s Islamist revolution in Iran, describing it as an ‘anti-imperialist people’s struggle for independence, freedom and social justice’.

When Iranian Revolutionary Guards seized 52 American diplomats and citizens in 1979 and held them hostage for 14 months, Straight Left described the resultant international furore as ‘hostage hysteria’ and ‘an excuse for the creation of another wave of anti-Iranian hatred’.

Only one important foreign government saw the Iranian crisis this way – the Soviet Union. At the time, Straight Left’s star columnist was Andrew Rothstein, a Soviet agent who once recruited the atom bomb spy Melita Norwood.

Straight Left praised the Palestinian armed resistance as an anti-imperialist crusade, stating that ‘the PLO has found great support in the Third World and the socialist camp, with the USSR at its forefront’. It greeted the Russian invasion of Afghanistan by saying that the Red Army had ‘saved Afghanistan from Imperialism’, and numerous articles waxed lyrical about the great progress being made there under Soviet rule. A Labour source said Milne was unaware that Rothstein was a Soviet agent.

ON JANUARY 2, 1981, Milne made his debut as a writer in a national publication, the New Statesman. Here he insisted that the Afghans had not actually been invaded at all, but merely requested ‘assistance’ under their ‘Friendship Treaty’ with the Soviets. He wrote: ‘I fail to see why military and economic assistance to a progressive government, which is carrying out the most basic democratic reforms (education, women’s rights, land reform) in the teeth of opposition from a tribal and feudal-based, foreign-backed, reactionary rebellion, should be considered “imperialism”.’

The Russians were simply trying to help ‘the Afghan revolution’, he said, and Labour should be supporting their efforts.

Three years later, following a spell on The Economist, Milne joined The Guardian, where features editor Gott took him under his wing.

Gott was later forced to resign after the Russian defector Oleg Gordievsky claimed he had been a Russian ‘agent of influence’.

Gott denied this, but admitted in his resignation letter that he took ‘red gold’ in the form of foreign trips with his partner, paid for by the Soviets, where he met senior KGB officials. According to Sir Richard Dearlove, it is these old associations – with terrorist groups which openly advocated violence, Straight Left, Rothstein and Gott – which would arouse the deepest concern if Milne were ever to be subjected to security vetting in the event of Labour gaining power. A Labour source said Milne knew nothing about Gott’s trips.

Adding to these concerns, Sir Richard said, is the fact that Milne’s views seem barely to have shifted over the decades.

In his later Guardian columns, he often defended the ‘progress’ made by ‘socialist countries’ such as East Germany – just as he and his colleagues once did in Straight Left.

Milne has long-held and disturbing views on terrorist violence. As a reporter at The Guardian, he announced in the newsroom just hours after the 1984 IRA Brighton bombing that he thought it was a ‘very daring attack’. (A Labour source said ‘any suggestion he supported the IRA attack would be entirely false’.)

His attitude towards terrorist violence appears to be underpinned by his conviction that almost anything the ‘imperialist’ West does is bad, while its enemies, however brutal or indiscriminate, deserve sympathy.

Two days after the September 11, 2001 attacks on New York and Washington, he wrote a column criticising Americans for failing to see why they were ‘hated with such bitterness’ for their ‘unabashed national egotism and arrogance’.

After the 2003 invasion of Iraq, he applauded the brutal insurgency, saying this was ‘a classic resistance movement’ fighting ‘Iraq’s real war of liberation’.

In 2009, when the Iranian government brutally repressed hundreds of protesters and jailed and tortured thousands more, Milne was still defending the Ayatollahs’ regime. Sneering at the protesters as ‘Tehran’s gilded youth’, he blamed the West for the violence, along with President Obama’s misguided attempt to ‘reconstitute US hegemony in the region’.

While he was still at The Guardian, Milne’s closeness to Corbyn was already evident. Paul Anderson, who knew Milne from their days at Oxford and worked on The Guardian’s Comment pages during Milne’s spell as their editor, told the MoS: ‘After 9/11, Seumas was constantly on the phone to Corbyn, discussing the Stop The War Coalition Corbyn was putting together.’

Also talking to him daily, for 45 minutes at a time, was the Left-wing then-Labour MP George Galloway, who has described Milne as his closest friend. These discussions took up so much time, Mr Anderson said, that the newspaper’s Comment pages were often late. Mr Anderson was also on the Comment desk when news broke that Milne had chaired a lengthy conference session at the Russian resort of Sochi in October 2014, where he introduced and fielded questions after the speech by President Putin.

‘The reaction in the office was open-mouthed amazement,’ Mr Anderson said.

‘Almost anyone would consider Seumas’s views on the Soviet Union and Russia as eccentric.’

Indeed, by the time of the Sochi conference, Milne had defended Russian aggression against Ukraine and Georgia, suggested there were many good things about the Soviet Union under Stalin, and claimed that the number of Stalin’s victims had been exaggerated – triggering furious rows with colleagues.

After Sochi, he was quizzed by The Guardian’s then editor, Alan Rusbridger – and admitted the Russians had paid his expenses, since the paper had decided to boycott the event because of Russia’s recent annexation of the Crimea.

LIKE Sir Richard Dearlove, Professor Anthony Glees, director of the Centre for Security and Intelligence Studies at the University of Buckingham, believes Milne would be a liability were Labour to gain power. He told the MoS: ‘The Russians would not have taken even a minimal risk of having someone chair a conference like the one in Sochi unless they trusted him absolutely. And that in itself means we should not trust him.’

He, too, believes Milne would be unlikely to get clearance through developed vetting, which would affect relationships with our allies. ‘He would not get clearance to look at intelligence from our sister services in the US, Spain, France, Israel and elsewhere. His relationships with the Russians and in the Middle East would show up as red warnings for them, too.

‘At best, if Corbyn refused to ditch him, this would mean the UK would be starved of critically important intelligence, especially in counter-terrorism. At worst, it would precipitate a major crisis.’

Sir Richard Dearlove agreed: ‘Anyone with his sort of background could not be let anywhere near classified information. It would be out of the question.

‘I am alarmed enough by Corbyn’s past associations, but Milne’s put him beyond the pale. That means Corbyn could not make the judgments and decisions a PM has to make unless he stopped consulting him.’ Sir Richard added: ‘An elected Prime Minister has a right to see everything – and he or she needs to in order to do the job. But Mr Milne would not pass developed vetting, and so would be denied access to classified papers.

‘There would be a recommendation made by the head of MI5, who would have to see the PM and say, “This man cannot be allowed to see any classified information.” Either Corbyn would have to cut contact with him – or the head of MI5 would have to threaten to resign, and do it if he still refused. It would blow up into a major constitutional issue, and it would be huge.’

US intelligence veteran John Sipher, former head of the CIA’s Russia division who also served as a station chief in key capitals, said he had ‘no doubt’ that if Milne got a high-level government job, this would damage the special relationship. ‘This would be a troubling development for the US national security community,’ he said.

‘They would have to be confident Milne was not able to gain access. If there was a legitimate concern that Mr Corbyn would include Milne in intelligence-related discussions, the US would likely share less of its most sensitive information. In any event, having Milne in a position of importance would force US policymakers and intelligence professionals to rethink the existing relationship. It would no longer be business as usual.’

Sir Richard said he was speaking out now for a reason: ‘It is very important that this issue is aired now so that when there is an Election, voters know exactly what they’re doing.’

A Labour source said: ‘These are the same old smears from a discredited establishment determined to prevent the election of a radical Labour government because our plans to transform the country and end support for disastrous wars threaten their interests.

‘Richard Dearlove, who as head of MI6 was involved in the infamous dodgy dossier that helped take us into the illegal Iraq War, has no credibility on security threats whatsoever.’