Theresa May faces Brexit defeat if she breaks ‘personal’ promise on negotiations, Tory rebels warn

Rebellion over 'meaningful vote' will be relaunched next week if prime minister tries to wriggle out of commitment she gave

Theresa May has been warned of certain defeat next week if she breaks her “personal” promise to give MPs a decisive say on Brexit, if she has failed to reach a deal by the autumn.

Rebel Tories insisted the prime minister had “conceded” on the crucial issue in crisis talks in her office yesterday – the price for them calling off a revolt, amid dramatic scenes in the Commons.

Nicky Morgan, a leading pro-EU Tory, said the rebellion over the “meaningful vote” would be relaunched next week if Ms May refused to stand by the commitment given.

“It was the prime minister’s personal assurance that was very important to us and she has given us that,” the former education secretary said.

Anger is rising after ministers – under fierce pressure from pro-Brexit Conservatives – denied any firm pledges had been made.

The clash threatens a complete breakdown in trust between No 10 and pro-EU Tories, which would make last-gasp compromises in further nail-biting Commons votes more difficult.

It centres on an attempt to force the government to seek approval from MPs on the next steps if the Brussels talks are still deadlocked at the end of November – or if the Commons has rejected a deal.

That would increase the prospect of a “soft Brexit”, inside the customs union and single market, or of an attempt to delay withdrawal beyond next March – or even, perhaps, of MPs forcing a further referendum.

The revolt was only aborted after a group of around 15 pro-EU Tories – enough to defeat the government – met the prime minister and she backed down, they say.

Crucially, speaking to BBC Radio 4’s Today programme, Ms Morgan stressed the “original wording” of the motion would go back down for votes next week, if Ms May went back on her word.

“Members of the House of Lords would also have the opportunity to put down a further amendment in relation to this,” she warned.

“I think there are a group of us who feel very strongly that parliament must have a real say in all circumstances.”

Early today, Robert Buckland, the solicitor general, played tough with the rebels – insisting there was only a “reasonable expectation” that “something will emerge” from their talks, to start immediately.

“I have a problem, both constitutionally and politically, with the concept of a direction being given by parliament,” he said.

And he added: “I think it's very important to remember that we mustn't tie the hands of the government in these all-important negotiations.”

But Dominic Grieve, the former attorney general behind the revolt, also made clear his amendment would be passed if the promise was broken, saying: “Obviously, this isn’t the end of the matter.

“Ultimately it is very likely that this amendment will come back from the Lords and so can be reconsidered.”

Both sides say there is no agreement on the third part of it, which would require the government to follow any “direction” given by MPs if there is no agreement by 15 February 2019.

The dilemma for the prime minister is that giving way to the rebels increases the chances of a confidence vote forced by her Brexiteers.

One, Iain Duncan Smith, told The Sun: “A veto over the government’s negotiations is unacceptable. It’s not going to happen.”