EU: No trade deal with Britain until key Brexit terms decided

European Union leaders on Saturday finished a special European summit on Brexit where they endorsed a stiff set of terms for negotiations with the U.K. over its departure from the bloc.

European Council president Donald Tusk said in a tweet Saturday: "Guidelines adopted unanimously. EU 27 firm and fair political mandate for the Brexit talks is ready."

It came as leaders of 27 EU nations met in Brussels without British Prime Minister Theresa May. The negotiations are likely to begin after Britain holds snap elections on June 8.

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The guidelineswill bind Michel Barnier, the EU'schief negotiator, toseek a deal that secures the rights of threemillion EU expats living in Britain, ensure London pays tens of billions of eurosBrussels thinks it will be owed.

They also rule out discussing the free trade deal May wantsuntil they see progress on agreeing those key withdrawal terms.

Before discussing the future, we have to sort out ourpast.- European Council President Donald Tusk

"Before discussing the future, we have to sort out ourpast," Tusk said as leaders gathered.

Another stumbling block to negotiations: EU Commission president Jean-Claude Juncker saidBritain currently blocks the decision-making on a review of the EU's long-term budget, and he sees a link with the upcoming talks. Junckersaid, "It would be good and it would make the start of the talks easier if Britain could lift its objection."

EU unity 'in the U.K.'s interest'

Talks set off on a positive note as the 27 member countries agreed to stick together against British efforts to divide and conquer.

"Maybe the British government will do its utmost tosplit the 27 nations, and it is trap we need to avoid," said Belgium's Prime Minister Charles Michel.

And he said Britain should harbour no illusion of getting out cheaply. "If you are no longer part of a club, it has consequences.A Brexit for free is not possible."

"We need to remain united," Tusk said. "It is onlythen that we will be able to conclude the negotiations, which means thatour unity is also in the U.K.'s interest."

One contentious issue for the bloc will be which countries scoop theprizes of hosting two EU agencies set to be moved from London.

Maybe the British government will do its utmost tosplit the 27 nations, and it is trap we need to avoid.- BelgianPrime Minister Charles Michel

Most of the 27 members are offering to house the European MedicinesAgency (EMA) and several wanting the European Banking Authority(EBA).

Danish Prime Minister Lars Loekke Rasmussen said the bloc will decide in June on a series of guidelines and thata formal decision would be made in the fall on where the agencieswill be located.

He said the mood at the one-day meeting on the divorceproceedings with Britain was characterized by seriousness, addingthat "the divorce that we didn't want" would be a challenge notonly for the EU members but certainly for Britain.

The Northern Ireland question

In a mark of how last year'sBrexitvote has called intoquestion the unity of the United Kingdom itself, leaders offered Irish Prime MinisterEndaKenny a pledge thatNorthern Ireland, which voted againstBrexit, could join the bloc in the future if its people vote to unite with Ireland, an EU member state.

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The two share the island, and the difficulties of re-establishing a land border once Britain leaves are immense and politically fraught.

Ireland's Europe MinisterDaraMurphy told The Associated Press that a statement on the Northern Ireland issue was added to the minutes of the summit.

Future relations between Ireland and Britain, including how the border between Ireland and Northern Ireland would work with the U.K. outside the bloc, have emerged as a key problem to be addressed during theBrexittalks.