EU Powers Rule Out Informal Exit Talks For UK

France, Germany and Italy have agreed there will be no talks on Britain's exit from the European Union until the UK formally starts the process to leave.

But France's president argued that it was in the interest of all parties to move quickly to resolve the situation.

"We must not lose time, neither for dealing in a suitable way with the question of the United Kingdom's exit, not for providing a new impetus for the EU," Francois Hollande said at a news conference with German Chancellor Angela Merkel and Italian Prime Minister Matteo Renzi.

Ms Merkel has said that she understand the UK needs time to decide how to move forward, but at the news conference ruled any backroom deals.

"We are united that Article 50 must be activated and before this decision is taken no further steps can be taken," she said.

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German stocks were down 3% on Monday afternoon, and there are concerns the uncertainty will fuel more panic.

"We cannot afford to have a long period of uncertainty," she said. "I think that would not be good for either the EU's 27 member states or Britain. But I also understand that Britain needs a certain period of time to analyse the situation."

Prime Minister David Cameron has said that the formal process to leave may not start for several months , before a new Conservative Party leader is selected.

"The British government will not be triggering Article 50 at this stage," he told the House of Commons on Monday afternoon.

"Before we do we must determine the kind of relationship we want with EU.

"That is rightly something for the next Prime Minister and Cabinet to decide.

"I've also made this point to the Presidents of the European Council and the European Commission and I will make it clear again at the European council tomorrow."

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Mr Renzi said earlier that Britain's vote to leave the European Union could be a "great opportunity" for the rest of the bloc to make long-needed changes.

He said the EU must now focus "a bit more on social issues and a bit less on bureaucratic ones".

Mr Renzi added that the referendum outcome strengthened the arguments for reform that Italy had often put forward to its partners, and these now had a greater chance of success.

Ahead of the talks in Berlin, the German and French foreign ministers promised to strengthen the European Union following Britain's shock vote to leave.

"We will... take further steps toward a political union in Europe, and we invite the other European states to join us in this endeavour," Frank-Walter Steinmeier and Jean-Marc Ayrault said in a joint position paper.

The US Secretary of State, John Kerry, said the interests and values which have united Europe and the US for so long have not changed following the vote.

And he called on the rest of Europe not to seek revenge on the UK for voting to leave.

Earlier, European Parliament's chief Martin Schulz called on David Cameron to begin formal proceedings to leave the EU as early as Tuesday, when leaders are due to meet in Brussels.

The Czech foreign minister, Lubomir Zaoralek, speaking after talks with colleagues from Poland, Hungary, Slovakia, Germany and France, said a "fast and hasty integration" of the remaining 27 members of the EU would be a "bad response" to Brexit.

He said doing nothing would also be bad, but that popular support is needed for further integration and new EU policies.

Another meeting of foreign ministers of non-founding members of the EU is due to take place in Warsaw later.

Elsewhere, EU Commission President Jean-Claude Juncker has said the nearly 1,000 British nationals who work for the bloc's executive body will not have to leave their jobs.