Brexit vote irreversible, say EU leaders

"Leaders understand that some time is now needed to allow the dust to settle in the UK," European Council president Donald Tusk explained.

The position had been agreed on Sunday because of the political crisis in the UK.

But EU leaders "also expect the intentions of the UK government to be specified as soon as possible", Tusk added.

As one official from a member state put it, the message to British officials was: "You have a referendum, you deal with it."

That means Britain will have to trigger Article 50 before any discussion about its future relationship with the EU can start. Cameron, who will resign after the summer, said it would be for the next British government to decide.

“As of this evening, I see no way back from the Brexit vote,” German chancellor Angela Merkel told journalists. “This is no time for wishful thinking, but rather to grasp reality.”

The message was delivered to Cameron but was in reality addressed to his successor and to eurosceptic leaders in Europe.

Many member states want to discourage British officials from trying to negotiate a new deal to stay in the EU as they fear this would give an incentive to other countries or anti-EU parties to threaten the EU with referendums.

If talks were held outside the legal framework of Article 50, "what kind of message would you send to everybody else?" the member state official said.

UK 'cannot cherry-pick EU rules'

The mood at the working dinner, the first since last Thursday's referendum and the last for Cameron, was "emotional", sources said.

Cameron himself told journalists how several leaders told stories of old links between the UK and their countries.

He said that the discussions were "very constructive, positive, calm" and that there was "an understanding that Britain and the EU should seek the closest possible relations... over trade, cooperation, security".

He added however that it would be "impossible to have all of the benefits of EU membership without some of the cost of membership".

"That is something the next British government is going to have to think through very carefully," he added.

Officials said that when the UK negotiates its new status with the EU, "there will be no cherry-picking" of EU rules.

'Face the consequences'

In particular, if it wants to get access to the EU single market, it will have to accept the freedom of movement for goods, capitals, services and above all for people.

"Freedom of movement is not subject to discussion, even if it has been portrayed in a cartoonesque way in the British press," a senior EU official said, adding that it was "a principle of the EU, we will not move from that".

“This isn’t to punish the British people but they will have to face the consequences for some time,” French president Francois Hollande said.

The issue is likely to be one of the most contentious ones in future talks.

Cameron himself told his colleagues during the discussion that he lost the referendum because he did not get a deal to reduce migration further.

“I think people recognised the strength of the economic case for staying, but there was a very strong concern about freedom of movement,” he told journalists.

In their summit conclusions, EU leaders only mentioned that "the UK prime minister informed the European Council about the outcome of the referendum in the UK", thus keeping their hands free for the months to come.

The Conservatives aim to choose a new leader, who will then become prime minister, by 9 September, party officials said on Tuesday.

'No need to speculate'

EU officials said Article 50 could be activated by the new prime minister in October, at the next EU summit, or later according to the domestic situation. But no time-frame was discussed by leaders, sources said.

At the press conference following the meeting, European Commission president Jean-Claude Juncker surprised everyone by saying that a prime minister from the Remain camp would have two weeks to notify Article 50, while for a PM from the Leave camp "it should be done on the day after his appointment".

An official told EUobserver that the remark was only made "in the heat" of the press conference.

Speaking after Juncker, Tusk said that there was "no need to speculate".

"If they [the future British cabinet] need more time we'll have to wait. It's not the best solution for the UK and for us but this is the only legal way we have today," he said.