The prime minister travelled to the EU capital on Wednesday night to meet Jean-Claude Juncker and try to convince the bloc to change the agreement to make it more palatable to Tory MPs.
Senior Tories were reportedly upbeat ahead of the meeting, trailing the prospect of the prime minister returning to London with concessions, but the message was not matched by officials in Brussels.
“I have great respect for Theresa May, for her courage and her assertiveness. We will have friendly talk tomorrow but I don’t expect a breakthrough,” Mr Juncker said ahead of the meeting.
Asked about the visit, a spokesperson for the European Commission told reporters in Brussels on Wednesday: “Each time that the prime minister expresses her wish to come we will always be happy to listen to her and see what she has to say.”
He confirmed the leaders were not planning to hold a press conference or take questions during the trip.
Following the meeting, the UK and EU leaders released a joint statement. It said the pair discussed what extra reassurances could be given to MPs, and “both reconfirmed their commitment to avoiding a hard border on the island of Ireland and to respect the integrity of the EU’s internal market and of the United Kingdom”.
Speaking on her way out of the meeting, the UK prime minister told reporters: “I’ve had a constructive meeting with President Juncker this evening. I’ve underlined the need for us to see legally binding changes to the backstop which ensure it cannot be indefinite, that’s what is required if a deal is going to pass the House of Commons.
“We’ve agreed that work to find a solution will continue at pace, time is of the essence and it’s in both our interests that when the UK leaves the EU it does so in an orderly way. And so we’ve made progress and the secretary of state for exiting the EU, the Brexit secretary, and the attorney general will be in Brussels tomorrow for further talks.”
Previous visits from the prime minister have also broken up without significant progress. Theresa May’s ministers Stephen Barclay and Geoffrey Cox also visited on Monday and are expected to return this week.
Speaking in Berlin ahead of the meeting Jeremy Hunt, the UK foreign secretary, said the EU would share responsibility for a damaging failure if there was a no deal.
He insisted that the UK government could get its Brexit deal through parliament despite a string of defeats, but only if there were legally binding changes to the backstop.
Mr Hunt said “the only way through the current situation” was for the EU to agree a change to the Irish backstop.
The foreign secretary added: “At this momentous time, a heavy responsibility falls upon all of us.”
“We do not want historians in the future to puzzle over our actions and ask themselves how it was that Europe failed to achieve an amicable change in its relationship with Britain – a country that is not simply a partner but a friend and ally in every possible sense.”
He said a failure to have reached a deal would mean the parties had “thereby afflicted grave and avoidable damage to our continent”.
Labour leader Jeremy Corbyn is expected to try his own luck in Brussels on Thursday, hot on the heels of the prime minister's visit. He and his Brexit chief Keir Starmer will meet with Michel Barnier, Martin Selmayr, and Guy Verhofstadt.
The visit will come after a string of senior EU figures have spoken out to welcome Labour’s proposals for a softer Brexit than the one planned by Theresa May.
Mr Barnier’s deputy Sabine Weyand said last week that Labour’s plans deserved to be examined, while European Council president Donald Tusk is said to have spoken well of the proposals in a previous private meeting with Theresa May.
Mr Verhofstadt also said he welcomed Mr Corbyn’s letter to the prime minister, which called for a cross-party compromise that included a customs union, close alignment with the single market, adherence to EU workers’ rights, and “shared institutions and obligations”.
“The Conservative Government is running down the clock in an attempt to blackmail Parliament into accepting Theresa May’s bad deal over a chaotic no deal,“ Mr Corbyn said ahead of the trip.
“We are saying loud and clear that there is no majority for no deal, and Labour will be working with politicians across the house to prevent a no deal outcome which would be so damaging to our economy and communities. Labour respects the result of the referendum, but we do not support the Prime Minister’s damaging approach which is focused more on appeasing factions of her party than finding a sensible solution that works for the whole country.
“With just 37 days until Brexit, Theresa May must accept that her historic defeats in Parliament and complete failure to reach a new deal mean her approach has failed. She should abandon her damaging red lines and finally work with Labour to reach a deal which works for our country.”
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