The European Commission’s spokesman said “no solution” is in sight as British ministers left Brussels on Wednesday without securing progress and saying only that talks had been “robust”.
Yet the countdown to a meaningful vote on Ms May’s deal – improved or not – continues, with the prime minister expected to make some kind of intervention towards the weekend to try and convince her MPs to back it either way.
Downing Street insiders accepted that if her deal fails to pass through the Commons on Tuesday, the government will likely lose control of the withdrawal schedule, with the Commons taking hold of the process to delay Brexit.
It came as Labour’s Jeremy Corbyn met senior Tory backbenchers proposing the UK enter a Norway-plus relationship with the EU, which would keep the UK in the single market and customs union, maintaining free movement and losing the ability to seal trade deals.
Brexit secretary Stephen Barclay and attorney general Geoffrey Cox left Brussels on Wednesday without having secured the changes to the withdrawal agreement that they need to make it more palatable to Eurosceptic Tory backbenchers.
Mr Cox said as he left: “These are very sensitive discussions, we are in the meat of the matter now. We’ve put forward some proposals, very reasonable proposals, are we are now really into the detail of the discussion.”
“Both sides have exchanged robust strong views,” he added.
An EU Commission spokesman told reporters in Brussels that “while the talks take place in a constructive atmosphere, discussions have been difficult” and that “no solution has been identified at this point that is consistent with the withdrawal agreement”.
In a sign that talks were moving at a slow pace, Leo Varadkar, the Irish prime minister, said shortly before the meeting that he still had not seen any “legal texts or draft legal texts to consider”.
While the two ministers’ empty-handed return was seen as a gloomy sign for the prime minister’s efforts to secure changes, there is still a little time in which her prospects of success could improve – technical talks will continue in Brussels and Mr Cox is expected to go back out on Friday.
No 10 officials indicated it would be likely that the prime minister would be out and about as the weekend approached making the case for the withdrawal agreement, potentially even making a speech, regardless of whether changes are locked-in.
Insiders have indicated that the practical deadline for securing any tweaks to the agreement is Sunday night, with it still being a possibility that Ms May travels to Brussels to sign off changes with the commission president Jean Claude Juncker that evening.
Things must be wrapped up in Brussels by then, because the government must on Monday afternoon table the Commons motion calling for the deal to be approved.
Any changes also need to be shown to Ms May’s Eurosceptic MPs and her DUP partners in government, before the actual vote takes place by Tuesday.
Ms May’s spokesman said: “We are absolutely working to secure changes to the backstop to ensure we can’t be trapped in it indefinitely, there’s more still to do but that work is ongoing.
“The second point is we have given the commitment we will hold the meaningful vote by the 12th and we stand by that.”
The Irish backstop will come into force if no new trading arrangement is struck between the UK and EU by the end of 2020 and it would see Britain potentially locked against its will into a customs union with the bloc.
Ms May’s spokesman went on: “I don’t think anybody was ever under any illusion that this wouldn’t be a difficult process and so it’s proving.”
If the prime minister fails to secure adequate changes to bring rebel Tories and the DUP on board, and the vote is lost on Tuesday, then there will be further votes on Wednesday, on whether to leave the EU without a deal or not, and then on Thursday, on whether to extend the Article 50 negotiating period, essentially delaying Brexit.
One No 10 insider said at that point the government would likely lose control of Brexit with former minister Oliver Letwin set to bring forward a proposal to give MPs control of the parliamentary schedule.
But any delay backed by the commons would still need to be approved by the European Council, with EU leaders likely to demand a price – possibly the UK staying in a customs union or some other kind of softer Brexit.
Mr Corbyn held talks on Wednesday with former ministers Sir Oliver Letwin and Nick Boles, part of a cross-party group who support the so-called Common Market 2.0 model of a close economic relationship.
Mr Boles said: “For months now we have been meeting with senior MPs from all parties in search of a cross-party Brexit compromise.”
Mr Kinnock said they had a “very detailed and constructive conversation”, adding: “There is a strong and growing cross-party consensus for a pragmatic, bridge-building Brexit.”
A Labour spokesman said the meeting was to “discuss how to achieve a deal that would be good for jobs and could bring Leave and Remain voters together”.
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