Boris Johnson will face a race against time to sell his last-minute deal to MPs before a crunch vote as he returns from Brussels in a “very confident” mood.
The Prime Minister said there is a “very good case” for MPs to vote in his favour in what is expected to be a dramatic and historic House of Commons showdown on Saturday.
But with significant opposition lining up to thwart it, he faces an uphill battle to get the deal through in the extraordinary sitting of Parliament – the first on a weekend since April 1982.
Mr Johnson’s key and influential allies in the DUP have already rejected his departure agreement, while the SNP has tabled an amendment to reject the deal demanding an immediate extension to the October 31 deadline and a general election.
The SNP’s parliamentary leader Ian Blackford – who said Scotland is being “royally shafted” – said opposition parties need to “quit dithering, back our amendment, and finally act to bring this appalling Tory government down and stop Brexit”.
Nicola Sturgeon has ruled out her MPs in the SNP backing the deal, insisting it will mean Scotland alone is “treated unfairly” when the UK leaves.
Jeremy Corbyn was quick to dismiss the PM’s agreement, criticising it for creating a customs border in the Irish sea, and saying: “As it stands we cannot support this deal.”
On Wednesday, Mr Johnson reportedly told the backbench 1922 Committee that the Government was close to a deal – on Hillary Step approaching Everest’s summit – but Jacob Rees-Mogg opted to make a reference to Greek mythology in praise of the agreement.
Writing in the Daily Telegraph, the Leader of the House of Commons said: “Like Jason in search of the golden fleece, the Prime Minister has overcome the mightiest of obstacles to return with a deal that fulfils the mandate of the referendum vote.
“Let us stagnate no more. Let us speculate no more. Let us spring forth, this deal held firmly in our hands and seize the victory the British people voted for.”
Meanwhile, Labour MP Hilary Benn has written a letter to Brexit Secretary Stephen Barclay asking for the Government to release an impact assessment for the deal before Saturday’s vote.
But Chancellor Sajid Javid appeared to refuse the request when he said there was “no need” for an impact assessment, according to Sky News.
Making Saturday even more crucial, the European Parliament’s chief Brexit official, Guy Verhofstadt, said the EU legislature will take its full time to carefully examine and approve any divorce deal.
He said MEPs will only start their work once the UK Parliament has passed a fully binding Brexit deal, and if that slips past the European plenary session next week, it may have to be picked up in the session that begins on November 13.
Mr Johnson has urged parliamentarians to “come together and get this thing done” after EU leaders approved the deal before the key summit began in Brussels on Thursday.
He appealed to those in Northern Ireland as well as across party lines in order to encourage support for the deal.
“I am very confident that when my colleagues in Parliament study this agreement that they will want to vote for it on Saturday and in succeeding days,” he said.
Appealing to Arlene Foster’s DUP, he insisted the country can leave the bloc “as one United Kingdom” and “decide our future together”.
EU Commission president Jean-Claude Juncker piled the pressure on MPs to back the deal in the parliamentary showdown by raising doubts over any further delay to the UK’s departure past October 31.
The Daily Telegraph reported that between 10 and 15 Labour MPs are prepared to back the deal to avoid a no-deal scenario, and the same newspaper said it learned that Mr Juncker agreed to play down the possibility of an extension after asking Mr Johnson what would help to get the support of MPs.
But European Council President Donald Tusk said if there is a request for an extension he will “consult with other member states to see how they react”.
Following days of intense negotiations, the PM announced that he had struck a “great new deal” shortly before heading to the Brussels meeting.
But it must still be passed by a Parliament which has so far proved hostile to both Brexit and Mr Johnson.
On Thursday, MPs approved a motion to hold the first weekend sitting of Parliament since the Falklands conflict, and if Parliament does not vote for the agreement on Saturday, Mr Johnson faces an almighty clash over whether he will request a further Brexit delay from Brussels as he is compelled to under the Benn Act.
The stance of the DUP is particularly important because the party wields influence over some hardline Tory Brexiteers and Mr Johnson is far short of a majority in Parliament.
In an attempt to persuade the doubters, Commons leader and former ERG chair Jacob Rees-Mogg said he thought the deal is “a triumph of negotiating”.
A total of 635 votes will be in play when the deal is debated, which means the Government will need at least 318 votes to be certain of a majority.
If every Conservative MP who is able to vote also backs the deal, this gives the Government 285 votes.
Mr Johnson did not rule out suspending the whip from Tories who rebelled on Saturday, or say whether he would welcome back the 21 he exiled for previously voting against his will.
Mr Johnson also has the backing of former Prime Minister David Cameron, who said he would back the deal if he were still an MP.
Speaking at Harrogate’s Crown Hotel on the first night of the town’s literature festival, Mr Cameron said: “I think it’s much better to leave with a deal, and I think Boris has done well to achieve that deal. I hope he’ll get it through parliament, I suspect he will but it will be tight.”