Theresa May touched down in Strasbourg tonight for last-minute Brexit talks with European Commission president Jean-Claude Juncker and other EU leaders.
The Prime Minister's meeting was confirmed by Downing Street on Monday evening.
It will be Mrs May's final throw of the dice ahead of Tuesday's Commons vote on her Withdrawal Agreement.
The talks with Mr Juncker will be one last opportunity to secure legal assurances on the Irish backstop - and in doing so secure the vital support of hardline Tory Brexiteers and the DUP.
Ministers in the Irish cabinet were also summoned to an emergency government meeting on Brexit.
The Irish premier, Leo Varadkar, who was due to begin his journey to the US for St Patrick's Day, returned from Dublin airport and was brought back to government buildings for the cabinet briefing.
A government source confirmed the hastily-arranged meeting took place at 7pm on Monday night.
Guy Verhofstadt, the European Parliment's Brexit coordinator, confirmed he and EP president Antonio Tajani will also meet Theresa May tonight.
He tweeted: "Meeting with @theresa-may & @EP-President tonight. I hope progress can be made, if it is possible, as a no deal £Brexit would be a catastrophe. We will stand by Ireland & the need to safeguard the Good Friday Agreement."
One of those Tory Brexiteers, Iain Duncan Smith, responded to the news by telling the BBC "I think they are reaching the point where they are about to have some kind of agreement".
However, he added his support - and that of the influential European Research Group - would be dependent on the verdict of its "group of legal people" which will pore over any proposal coming out of Strasbourg.
A statement to the Commons by Brexit secretary Stephen Barclay has been put back to about 10pm as a result of Mrs May's talks.
The negotiations are a boost for Number 10 after Michel Barnier, the EU’s chief negotiator, said earlier on Monday there would be no more high-level backstop talks.
Mr Barnier had claimed the only talks that mattered were “between the Government in London and the Parliament in London”.
Mrs May had earlier ducked a demand from Labour leader Jeremy Corbyn to update the House of Commons on the progress of negotiations, sending Brexit minister Robin Walker to respond to his urgent question in her place.
If her deal is defeated on Tuesday, MPs will then vote on Wednesday whether to support a no-deal Brexit.
If a no-deal Brexit is rejected, members will get a vote on Thursday on requesting an extension to Article 50 and delaying EU withdrawal.
