The European Parliament on Tuesday called for an 'immediate' triggering of Brexit.
Britain faced angry calls from other European leaders to act quickly to resolve the political and economic chaos unleashed by its vote to leave the European Union which the IMF said could put pressure on global growth, media reports said on Tuesday.
"This process should start as soon as possible," Xinhua news agency quoted German Foreign Minister Frank Walter Steinmeier as saying after a meeting with his counterparts from France, Italy, the Netherlands, Belgium and Luxembourg in Berlin.
The aim must be "not to fall into a prolonged stalemate," he added.
"We will start immediately," said French Foreign Minister Jean-Marc Ayrault, adding "we now expect that the process will be triggered under Article 50."
Meanwhile, the EU parliament, which is holding a special session ahead of a meeting between EU chief Jean-Claude Juncker and UK Prime Minister David Cameron -- the first such meeting since the UK's referendum -- later on Tuesday, witnessed bitter confrontation with leading Leave campaigner, UKIP's Nigel Farage being booed and at one point accused of using "Nazi propaganda".
While asserting that the will of the British people must be respected, Juncker targeted Farage, saying: "To some extent I am really surprised that you are here. You were fighting for the exit, the British people voted in favour of the exit. Why are you here?"
He also accused Farage of lying about using the UK's EU contributions to fund the country's National Health Service, saying he had "fabricated reality".
Belgian ex-PM Guy Verhofstadt, and leader of the liberal group in the European parliament, said Farage had used "Nazi propaganda" in the campaign, referring to a poster showing lines of refugees.
Farage later hit back at EU parliamentarians, saying: "I know that virtually none of you have ever done a proper job in your lives or worked in business or worked in trade or indeed ever created a job. But listen, just listen."
"Isn't it funny? When I came here 17 years ago and I said that I wanted to lead a campaign go get Britain out of the European Union, you all laughed at me. Well, I have to say, you’re not laughing now, are you?"
"And the reason youare so upset, the reason you are so angry, has been perfectly clear from all the angry exchanges this morning. You, as a political project, are in denial. You are in denial that your currency is failing."
"But the biggest problem you’ve got, and the main reason the United Kingdom voted the way that it did, is that you have, by stealth, by deception, without ever telling the truth to the British or the rest of the people's of Europe, you have imposed upon them a political union."
"And when the people in 2005 in the Netherlands and France voted against the political union, when they rejected the constitution, you simply ignored them and brought the Lisbon treaty in through the back door," he said, amidst booing by EU members.
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.
Earlier, Merkel, speaking at a press conference in Potsdam, outside Berlin, prodded for British action.
"To be honest, it shouldn't take forever, that's right -- but I would not fight over a short period of time," Merkel said.
The British side is much more relaxed. Prime Minister David Cameron has said that his successor, to be chosen by October, should start the formal exit process.
Image: Nigel Farage, leader of the United Kingdom Independence Party and Member of the European Parliament holds a British Union Jack flag. Photograph: Vincent Kessler/File Photo/Reuters