There have been bitter exchanges in the European parliament during a debate on the UK’s vote to leave the EU.
Much of the anger was aimed at leading Leave campaigner, UKIP’s Nigel Farage, who was booed and at one point accused of using “Nazi propaganda”.
But in his speech Mr Farage told parliament members “you as a political project are in denial”.
He said hardly any of them had ever done a proper job in their lives, or created one.
The parliament was holding a special session ahead of a meeting between EU leader and UK Prime Minister David Cameron – the first such meeting since the UK’s vote later on Tuesday.
Mr Cameron is stepping down, saying it will be up to his successor to trigger the formal method by which the country leaves the EU, and to conduct exit negotiations.
In his statement to the parliament, Mr Juncker said the will of the British people must be respected, prompting applause from UK Independence Party (UKIP) leader Nigel Farage, a key campaigner behind the leave vote.
“You were fighting for the exit, the British people voted in favour of the exit. Why are you here?” Mr Junker said to him.
He also accused Mr Farage of lying about using the UK’s EU contributions to fund the country’s National Health Service, saying he had “fabricated reality”.
Others went much further. Belgian ex-PM Guy Verhofstadt, and leader of the liberal group in the European parliament, said Mr Farage had used “Nazi propaganda” in the campaign, referring to a poster showing lines of refugees.
In a veiled condemnation of Leave campaigner Boris Johnson, and likely contender to be the next British Prime Minister, Mr Verhofstadt attacked “the selfishness of one man prepared to do anything to become the prime minister of the UK”.
Manfred Weber, the chairman of the European People’s Party grouping, said: “The times of appeasement are over. We have to stand up for our European project.”
“Apologise to the British, shame on you,” he told Mr Farage, adding: “Stop this populist Brussels bashing.”
Hitting back, Mr Farage told parliament that they were “in denial”.
“We now offer a beacon of hope to democrats across the European continent,” he said. “The UK will not be the last member state to leave the EU.”
France’s National Front leader Marine Le Pen, who wants her country to hold a referendum on EU membership, told MEPs to “put away those sulky looks and rejoice in the emancipation” of the British people.
Meanwhile in a speech to the German parliament, Chancellor Angela Merkel said that the EU was strong enough to survive without the UK.
She said she respected the result, but warned the bloc would not tolerate British “cherry-picking” when it came to negotiations.