British relations with the EU have hit a new low after Theresa May launched a venomous attack on European politicians – accusing them of meddling in the UK’s general election and trying to wreck Brexit.

The Prime Minister spoke outside Downing Street to charge top EU figures with making threats, “deliberately” attempting to swing the 8 June vote and trying to torpedo negotiations.

The ferocity of the speech stunned Westminster and sent shockwaves all the way to Brussels where senior figures remained tight-lipped in the wake of the attack, while domestic rivals accused Ms May of irresponsible electioneering and mimicking Donald Trump in “winding up” scraps with foreign leaders.

Hours earlier the European Commission cemented a tough negotiating stance after new estimates emerged of the potential size of the UK’s “divorce bill” – putting it as high as €100bn (£84bn).

Ms May’s unusual intervention also comes amid fallout over leaked details of a meeting between her and Jean Claude Juncker, which led a German newspaper to report how the European Commission President thinks Ms May is “deluding herself” on Brexit.

The PM had just arrived back from Buckingham Palace to mark the dissolution of Parliament, when she emerged from No 10 to say: “In the last few days, we have seen just how tough these talks are likely to be.

“Britain’s negotiating position in Europe has been misrepresented in the continental press. The European Commission’s negotiating stance has hardened. Threats against Britain have been issued by European politicians and officials.

“All of these acts have been deliberately timed to affect the result of the general election that will take place on 8 June.”

UK General Election 2017 Show all 47 1 /47 UK General Election 2017 UK General Election 2017 12 June 2017 British Prime Minister Theresa May leaves 10 Downing Street for the 1922 committee on June 12, 2017 in London, England. British Prime Minister Theresa May held her first cabinet meeting with her re-shuffled team today Getty Images UK General Election 2017 12 June 2017 DUP leader Arlene Foster stands alongside deputy leader Nigel Dodds as they hold a press conference at Stormont Castle as the Stormont assembly power sharing negotiations reconvene following the general election on June 12, 2017 in Belfast, Northern Ireland. Discussions between the DUP and the Conservative party are also continuing in the wake of the UK general election as Prime Minister Theresa May looks to form a government with the help of the Democratic Unionist parties ten Westminster seats. 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Getty Images UK General Election 2017 12 June 2017 British Prime Minister Theresa May (C, L) holds the first Cabinet meeting of her new team. Getty UK General Election 2017 11 June 2017 British Prime Minister Theresa May attends church in her constituency with her husband Philip May, a few days after disappointing results in a general election. Rex Features UK General Election 2017 9 June 2017 Leader of the Labour Party Jeremy Corbyn leaves Labour Party HQ this morning, following a general election yesterday. Parliament is hung, with no individual party gaining an overall majority. Post general election reaction. Rex UK General Election 2017 9 June 2017 BELFAST, NORTHERN IRELAND - JUNE 09: DUP leader and Northern Ireland former First Minister Arlene Foster (C) holds a brief press conference with the DUP's newly elected Westminster candidates who stood in the general election Getty Images UK General Election 2017 9 June 2017 A " Get May Out" demo took place opposite the gates of Downing Street, calling for May to resign, after the shock election results and Mays coalition with the DUP. Rex Features UK General Election 2017 9 June 2017 A demonstrator wears a mask depicting Britain's Prime Minister and leader of the Conservative Party Theresa May, poses with a mock gravestone bearing the words "Hard Brexit, RIP", during a protest photocall near the entrance 10 Downing Street in central London AFP/Getty Images UK General Election 2017 9 June 2017 Britain's Prime Minister Theresa May arrives at the Conservative Party's headquarters in London Reuters UK General Election 2017 9 June 2017 Britain's Prime Minister and leader of the Conservative Party Theresa May flanked by her husband Philip delivers a statement outside 10 Downing Street in central Londo Getty UK General Election 2017 9 June 2017 Britain's Prime Minister and leader of the Conservative Party Theresa May leaves Buckingham Palace in London the day after a general election in which the Conservatives lost their majority Getty Images UK General Election 2017 9 June 2017 A TV cameraman watches the door of 10 Downing Street in London Getty Images UK General Election 2017 9 June 2017 Labour leader Jeremy Corbyn is greeted by his Office Director Karie Murphy as he arrives at Labour Party HQ in Westminster, London, after he called on the Prime Minister to resign, saying she should 'go and make way for a government that is truly representative of this country' Dominic Lipinski/PA Wire UK General Election 2017 9 June 2017 Britain's Prime Minister Theresa May arrives at the Conservative Party's headquarters with her husband Philip in London REUTERS/Peter Nicholls UK General Election 2017 9 June 2017 Ukip leader Paul Nuttall speaks during a press conference at Boston West Golf Club where he announced that he is standing down as party leader Joe Giddens/PA UK General Election 2017 9 June 2017 Ruth Davidson, leader of the Scottish Conservatives, leaves the counting centre for Britain's general election with her partner Jen Wilson in Edinburgh, Scotland REUTERS/Russell Cheyne UK General Election 2017 9 June 2017 Scottish Labour leader Kezia Dugdale celebrates with candidate for Edinburgh South Ian Murray as he retains his seat at the Meadowbank Sports Centre counting centre in Edinburgh, Scotland Getty Images UK General Election 2017 9 June 2017 First Minister Nicola Sturgeon speaks to the media at the Emirates Arena in Glasgow, as counting is under way for the General Election Andrew Milligan/PA Wire UK General Election 2017 9 June 2017 Scottish Conservative leader Ruth Davidson at Meadowbank Sports Centre in Edinburgh, as counting is under way for the General Election PA UK General Election 2017 9 June 2017 Scottish National Party (SNP) leader Nicola Sturgeon reacts at the Emirates Arena in Glasgow, Scotland EPA UK General Election 2017 9 June 2017 Jeremy Corbyn, leader of Britain's opposition Labour Party, arrives at the Labour Party's Headquarters in London REUTERS/Marko Djurica UK General Election 2017 9 June 2017 UKIP Leader Paul Nuttall leaves in a car following the vote count for the constituency of Boston and Skegness in Boston, England Anthony Devlin/Getty Images UK General Election 2017 9 June 2017 British Prime Minister and Conservative Party leader Theresa May speaks at the declaration at the election count at the Magnet Leisure Centre in Maidenhead, England. Getty Images UK General Election 2017 8 June 2017 A policer officer enters a polling station in London AP UK General Election 2017 8 June 2017 A woman leaves after casting her vote at the Hove Museum and Art Gallery near Brighton, in southern England Getty UK General Election 2017 8 June 2017 A polling station sign is seen on a telephone box outside the polling station at Rotherwick Hall, west of London Getty UK General Election 2017 7 June 2017 A woman walks past a general election display in the window of a betting shop in Camden on June 7, 2017 in London, United Kingdom. Britain goes to the polls tomorrow, Getty Images UK General Election 2017 7 June 2017 Britain's Prime Minister Theresa May visits Atherley Bowling Club during an election campaign visit on June 7, 2017 in Southampton, England. Britain goes to the polls tomorrow June 8 to vote in a general election. Getty Images UK General Election 2017 6 June 2017 A supporter wears a pair of Jeremy Corbyn decorated tights at a general election campaign event in Birmingham, central England, on June 6, 2017. Britain goes to the polls on June 8 to vote in a general election only days after another deadly terror attack in the nation's captial. AFP/Getty Images UK General Election 2017 6 June 2017 A picture taken in London, shows election leaflets from various parties displayed ahead of the United Kingdom's general elections. Britain goes to the polls on June 8 to vote in a general election only days after another terrorist attack on the nation's capital AFP/Getty Images UK General Election 2017 6 June 2017 Election workers, George Gaunt and Luca Tragid deliver the first ballot boxes, on the Royal Mile in Edinburgh AFP UK General Election 2017 6 June 2017 British Prime Minister Theresa May meets with Conservative party supporters during an election campaign visit to a bakery during an election campaign visit on June 6, 2017 in Fleetwood, north-west England. 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If elected in next week's general election Mr Corbyn is pledging to create a million new jobs and to scrap zero-hours contracts Getty Images UK General Election 2017 1 June 2017 Scottish Conservative and Unionist Party leader Ruth Davidson joins a selection of Scottish Conservative election candidates and activists during campaigning on May 1, 2017 in South Queensferry, Scotland. With only seven days to go until the general election on June 8th, polls are showing the SNP out in front and the Conservatives set to close in on Labour. Getty Images UK General Election 2017 29 May 2017 Prime Minister Theresa May canvasses in Richmond with Conservative candidate Zac Goldsmith on May 29, 2017 in London, United Kingdom. After suffering defeat in the London Mayoral election Zac Goldsmith resigned over the Government's position on Heathrow expansion. He stood as an Independent but lost in a by-election to the Liberal Democrats. Britain goes to the polls on June 8 to elect a new parliament in a general election Getty Images UK General Election 2017 22 May 2017 Liberal Democrat leader Tim Farron poses for a selfie taken by carer April Preston during a General Election campaign visit to the Barlow Medical Centre, in Didsbury, Manchester Yui Mok/PA UK General Election 2017 22 May 2017 Britain's Prime Minister Theresa May speaks at an election campaign event in Wrexham, Wales Reuters UK General Election 2017 22 May 2017 Britain's main opposition Labour Party leader Jeremy Corbyn, and Labour's former deputy Prime Minister, John Prescott, exit the party's general election campaign 'battle' bus as they arrive at an event in Kingston upon Hull, northern England Getty Images UK General Election 2017 22 May 2017 Britain's main opposition Labour Party leader Jeremy Corbyn walks with supporters between venues, before speaking again at another general election campaign event in Kingston upon Hull, northern England Getty Images UK General Election 2017 22 May 2017 An anti-fox hunting protester is taken away and arrested by police outside the venue where Britain's Prime Minister Theresa May was due to launch the Welsh Conservative general election manifesto at Gresford Memorial Hall in the village of Gresford, near Wrexham, North Wales, on May 22, 2017. 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Ms May claimed that in contrast to the actions of European politicians, she had made clear in correspondence with Brussels that “Britain means no harm” and wants the EU project to be a success.

She went on: “But the events of the last few days have shown that – whatever our wishes, and however reasonable the positions of Europe’s other leaders – there are some in Brussels who do not want these talks to succeed, who do not want Britain to prosper.

“So now more than ever we need to be led by a Prime Minister and a Government that is strong and stable.”

Labour leader Mr Corbyn said Ms May was “playing party games with Brexit” in the hope of winning an advantage for the Tories in the election.

He went on: “By winding up the public confrontation with Brussels, the Prime Minister wants to wrap the Conservative Party in the Union Jack and distract attention from her Government’s economic failure and run-down of our public services.

“But Brexit is too important to be used as a political game in this election.”

Lib Dem EU spokesperson Nick Clegg said: “Theresa May’s desperate, bizarre statement could have come word for word from Nigel Farage.

David Davis says disastrous row between May and EU will help Conservatives win election

“The coalition of hard Brexit between the Conservatives and Ukip is now complete, and it will be hard-pressed families up and down the country who will suffer most.”

SNP leader Nicola Sturgeon criticised Ms May’s speech, saying it had created a “poison atmosphere [sic]” and was “deeply irresponsible.”

While Labour’s Chuka Umunna, a leading supporter of the Open Britain campaign pushing for a softer Brexit, accused Ms May of “straightforward, crude electioneering”.

He added: “This is straight out of the Donald Trump playbook – not what we expect from a British Prime Minister.”

How Brexit affected Britain's favourite foods from Weetabix to Marmite Show all 8 1 /8 How Brexit affected Britain's favourite foods from Weetabix to Marmite How Brexit affected Britain's favourite foods from Weetabix to Marmite Weetabix Chief executive of Weetabix Giles Turrell has warned that the price of one of the nation’s favourite breakfast are likely to go up this year by low-single digits in percentage terms. Reuters How Brexit affected Britain's favourite foods from Weetabix to Marmite Nescafé The cost of a 100g jar of Nescafé Original at Sainsbury’s has gone up 40p from £2.75 to £3.15 – a 14 per cent rise—since the Brexit vote. PA How Brexit affected Britain's favourite foods from Weetabix to Marmite Freddo When contacted by The Independent this month, a Mondelez spokesperson declined to discuss specific brands but confirmed that there would be "selective" price increases across its range despite the American multi-national confectionery giant reporting profits of $548m (£450m) in its last three-month financial period. Mondelez, which bought Cadbury in 2010, said rising commodity costs combined with the slump in the value of the pound had made its products more expensive to make. Cadbury How Brexit affected Britain's favourite foods from Weetabix to Marmite Mr Kipling cakes Premier Foods, the maker of Mr Kipling and Bisto gravy, said that it was considering price rises on a case-by-case basis Reuters How Brexit affected Britain's favourite foods from Weetabix to Marmite Walkers Crisps Walkers, owned by US giant PepsiCo, said "the weakened value of the pound" is affecting the import cost of some of its materials. A Walkers spokesman told the Press Association that a 32g standard bag was set to increase from 50p to 55p, and the larger grab bag from 75p to 80p. Getty How Brexit affected Britain's favourite foods from Weetabix to Marmite Marmite Tesco removed Marmite and other Unilever household brand from its website last October, after the manufacturer tried to raise its prices by about 10 per cent owing to sterling’s slump. Tesco and Unilever resolved their argument, but the price of Marmite has increased in UK supermarkets with the grocer reporting a 250g jar of Marmite will now cost Morrisons’ customers £2.64 - an increase of 12.5 per cent. Rex How Brexit affected Britain's favourite foods from Weetabix to Marmite Toblerone Toblerone came under fire in November after it increased the space between the distinctive triangles of its bars. Mondelez International, the company which makes the product, said the change was made due to price rises in recent months. Pixabay How Brexit affected Britain's favourite foods from Weetabix to Marmite Maltesers Maltesers, billed as the “lighter way to enjoy chocolate”, have also shrunk in size. Mars, which owns the brand, has reduced its pouch weight by 15 per cent. Mars said rising costs mean it had to make the unenviable decision between increasing its prices or reducing the weight of its Malteser packs. iStockphoto

During the US election Mr Trump repeatedly picked fights with foreign leaders, including politicians in Mexico and Europe, while promising to put “America first”.

In her speech Ms May appeared to cite leaks to the Frankfurter Allgemeine newspaper which had revealed details of Mr Juncker’s views of last Wednesday’s Downing Street meeting, with the resulting stories giving Ms May’s rivals ammunition in the on-going election.

The paper claimed Mr Juncker dismissed her plan to reach a deal on citizens’ rights by June as failing to appreciate the complexity of the matter – he reportedly took out copies of the EU’s Canada trade deal and Croatia’s EU entry deal to demonstrate how difficult a deal would be.

Afterwards, he is said to have called German Chancellor Angela Merkel, to tell her that Ms May lives “in another galaxy” and is “deluding herself” over Brexit.

Michel Barnier speaks in Brussels (Getty) (Getty Images)

German Europe minister Michael Roth tweeted how the British Government should “say goodbye to the fairy tale” that things will get better for Britain after Brexit, while the European Parliament’s Brexit co-ordinator Guy Verhofstadt mocked Ms May’s election campaign slogan, suggesting she lacked a “strong and stable” understanding of the complex issues around EU withdrawal.

There was a brief flash of the Prime Minister’s frustration over the leaks when she warned Mr Juncker on Tuesday how he would soon discover she is a “bloody difficult woman”, but her speech on the doorstep of No 10 bore her threat out as she ratcheted-up tensions with withdrawal talks yet to even begin.

This morning reports emerged that new estimates of the UK’s potential “divorce bill” put it at €100bn following an analysis of the latest French and German demands.

In Brussels, shortly before Ms May’s Downing Street speech, the EU’s chief Brexit negotiator Michel Barnier underlined that “there is no punishment, there is no Brexit bill”, but said the UK would have to commit to settle liabilities to stand any chance of a trade deal, along with agreeing a deal on citizens’ rights and external borders.

As he confirmed his negotiating directives, Mr Barnier said: “The UK must put a great deal of energy and effort into these three issues over the next weeks and months. That will increase the chances of reaching a deal.

“Some have created the illusion that Brexit would have no material impact on our lives or that negotiations can be concluded quickly and painlessly – this is not the case.”

He also signalled that Ms May could be forced to break her key Brexit election pledge to end the European Court of Justice’s influence, if she wants to secure the all import EU trade deal.

Mr Barnier said he wanted an “entente cordial” with the UK, but confirmed no trade talks can even begin until London accepts the Court would hold sway in Britain for years after Brexit, in particular to protect the rights of EU citizens still living here.

In colourful comments he said that during the “constructive” meeting at Downing Street, which he had also attended, he had discussed with Ms May their mutual love of mountain walking.

He went on: “If you like walking in the mountains you have to learn a number of rules. You have to learn to put one foot in front of the other, because sometimes you are on a steep and rocky path.