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 guidelines will bind Michel Barnier, the EU's chief negotiator, to seek a deal that secures the rights of three million EU expats living in Britain, ensure London pays tens of billions of euros Brussels thinks it will be owed.

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

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

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

Another stumbling block to negotiations: EU Commission president Jean-Claude Juncker said Britain currently blocks the decision-making on a review of the EU's long-term budget, and he sees a link with the upcoming talks. Juncker said, "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 to split 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 only then that we will be able to conclude the negotiations, which means that our unity is also in the U.K.'s interest." 

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

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

Most of the 27 members are offering to house the European Medicines Agency (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 that a formal decision would be made in the fall on where the agencies will be located.

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

The Northern Ireland question

In a mark of how last year's Brexit vote has called into question the unity of the United Kingdom itself, leaders offered Irish Prime Minister Enda Kenny a pledge that Northern Ireland, which voted against Brexit, 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 Minister Dara Murphy 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 the Brexit talks.