Theresa May (pictured in No10 last night) will hold crisis talks with Cabinet this morning before facing the House of Commons
Theresa May admitted her reworked Brexit deal might not be ready before March today as she faces another showdown with mutinous MPs.
The PM told Cabinet she needed 'a little more time' to get concessions on the Irish border backstop from the EU.
She made clear she will use a Commons statement later to urge politicians to 'hold their nerve', promising Remainer MPs another chance to influence the Brexit process by the end of the month if her renegotiation is not complete.
But there is little sign that the premier's battle to secure changes to the backstop - the insurance policy to avoid a hard border - is making progress.
EU chief negotiator Mr Barnier emerged from a dinner with Brexit Secretary Steve Barclay in Brussels last night to insist the Withdrawal Agreement will not be renegotiated.
The PM's spokesman said Mrs May gave ministers details of what had happened on her visit to Brussels last week, spelling out that she had suggested replacing the backstop with 'alternative arrangements', or inserting a time-limit or a 'unilateral exit mechanism'.
Mrs May told Cabinet it was 'clear that these discussions with the EU will need a little more time to conclude and so we will not be bringing forward a meaningful vote this week, but will table an amendable motion for debate on Thursday'.
'We will also commit to laying another amendable motion for debate by 27th February if a meaningful vote has not been passed by then,' the spokesman added.
Downing Street said Mrs May's statement, which comes a day earlier than expected, will give MPs more time to 'digest the content' ahead of the Valentine's Day votes.
Mrs May is expected to say: 'The talks are at a crucial stage. We now all need to hold our nerve to get the changes this House has required and deliver Brexit on time.
'By getting the changes we need to the backstop; by protecting and enhancing workers' rights and environmental protections; and by enhancing the role of Parliament in the next phase of negotiations I believe we can reach a deal that this House can support.'
Fevered speculation has been sweeping Westminster in the absence of any firm developments, with claims Mrs May is planning to quit in the summer if her package is finally passed by MPs.
Michel Barnier (pictured in Luxembourg yesterday) emerged from a dinner with Brexit Secretary Steve Barclay in Brussels last night to insist the divorce deal will not be renegotiated
Home Secretary Sajid Javid (left) and Justice Secretary David Gauke (right) were at the Cabinet meeting this morning
Aid Secretary Penny Mordaunt, a Brexiteer, was also in Downing Street for Cabinet today
There is also fresh chatter about a snap general election, fuelled by a YouGov poll suggesting the Tories could win a small effective majority.
Talks are continuing apace between the UK and EU, with Brexit Secretary Steve Barclay and Mrs May's de facto deputy, David Lidington, meeting MEPs in Strasbourg on Tuesday.
Mr Barclay was said to have held 'constructive' talks last night with the EU's Mr Barnier in Brussels.
After dining on pan-fried North Sea sole with Scottish scallops and Welsh samphire, the pair agreed to further meetings in the coming days, while their teams will continue to work to find a way forward.
However, Mr Barnier said afterwards: 'It's clear from our side that we are not going to reopen the withdrawal agreement but we will continue our discussion in the coming days.'
Meanwhile, Sky News reported the former president of the European Council, Herman Van Rompuy, had dinner with Mr Lidington in Brussels on Monday night.
Mr Van Rompuy has been tipped as a potential 'influencer' to break the Brexit deadlock, the broadcaster reported.
Negotiations of a kind have also been taking place back in Westminster, with an exchange of letters between Mrs May and Labour leader Jeremy Corbyn.
Commons Leader Andrea Leadsom today appealed for Brexiteers not to be 'purist' about the type of deal the PM can secure on the Irish backstop.
Asked if there would need to be changes to the Withdrawal Agreement, the prominent Leave supporter told BBC Radio 4's Today programme: 'The point is to ensure that the UK cannot be held in a backstop permanently.
'How it's achieved is not something to be purist about.'
Boris Johnson (pictured in Westminster yesterday) gave the PM a glimmer of hope by saying he could support her deal if there was a time limit on the backstop
What are the options for reworking the Irish border backstop?
The EU has flatly dismissed calls for the Withdrawal Agreement to be reopened.
But Theresa May has promised MPs that she will somehow get legally-binding changes that satisfy concerns about the Irish border backstop.
Here are some possible options for how the PM might seek to get through the impasse.
A unilateral exit clause
Prominent backbenchers including former Brexit Secretary Dominic Raab has pushed Mrs May to seek a unilateral get-out from the backstop.
The current mechanism can only be deactivated through a joint review system - although the EU insists it is technically 'temporary'.
But Brussels has insisted that an 'insurance policy' that can be ended by one side is not acceptable.
A hard end date to the backstop would allay the fears of most Tory MPs - as long as it is not too far in the future.
Boris Johnson has suggested he could vote for the deal if she manages to get a time limit, although he also said it should conclude before the next election in May 2022.
The former foreign secretary also unhelpfully insisted a legal 'codicil' - an amendment which would run alongside the Withdrawal Agreement - would not be enough to win him over and he wants the whole thing unpicked.
Again, the EU has insisted it will not agree to a backstop that is time limited.
The 'Malthouse Compromise'
Tory Remainers and Brexiteers have been working on a proposal to replace the backstop with a looser, Canada-style free trade arrangements. The plan would deploy technology in a bid to avoid a hard border.
But Brussels has already dismissed the technogical solutions as 'magical thinking', saying the systems needed do not yet exist.
Guarantees that the backstop will only be 'temporary'
The EU's top official, Martin Selmayr floated the idea of 'unzipping' the Withdrawal Agreement and inserting new guarantees about the 'temporary' nature of the backstop during meetings with MPs.
He suggested the text of recent letters from Donald Tusk and Jean-Claude Juncker could be cut and pasted in without reopening other terms.
But that would be highly unlikely to satisfy Brexiteers.
What will happen next in the unfolding Brexit drama?
MPs will hold another round of votes on Brexit.
They are not due to pass judgement on Theresa May's deal - instead debating a 'neutral' motion simply saying that they have considered the issue.
However, a range of amendments are set to be tabled. They could include proposals to delay the Brexit date beyond March 29.
Labour is pushing a change that would force another 'meaningful vote' on the PM's Brexit deal by February 26, regardless of whether she has finished renegotiating the package with the EU.
Mrs May could have an opportunity to seal a new package with fellow EU leaders at a joint summit with the Arab League in Sharm el-Sheikh.
However, it is not clear how many will attend the gathering - or whether she will have completed the deal by then.
Downing Street is trying to head off a potential Tory Remainer mutiny by promising MPs will get another set of votes by this date regardless of whether there is a final deal.
The PM will attend a scheduled EU summit in Brussels that would effectively be the last opportunity to get agreement.
Some MPs fear that Mrs May is trying to delay for as long as possible, and might even try to hold a make-or-break vote in the Commons on March 26. That would be just 72 hours before Brexit, giving them a very stark deal-or-no-deal choice.
11pm, March 29
The UK is due to leave the EU with or without a deal, unless the Article 50 process is extended with approval from the bloc's leaders, or revoked to cancel Brexit altogether.