Boris Johnson is returning to Downing Street after securing a new Brexit deal at a crucial Brussels summit – but he has a fight on his hands to get MPs to back it.
The stage is set for a Saturday vote in the Commons on the prime minister’s fresh agreement, with Mr Johnson hoping to succeed where predecessor Theresa May failed three times.
However, the outcome remains in the balance.
Northern Ireland’s Democratic Unionist Party – on whose support the hopes of passing a deal in parliament were widely seen as hinging upon – has said it cannot back what is on offer.
Labour, the Liberal Democrats and the SNP are also opposed, meaning the parliamentary arithmetic is looking tight.
However, a number of Conservative MPs who failed to back Mrs May’s deal have indicated they could support Mr Johnson’s agreement.
Meanwhile, efforts to win round Labour MPs representing constituencies that voted for Brexit in the 2016 referendum are likely to intensify in the hours leading up to Saturday’s vote.
The PM needs 320 votes to pass an agreement, presuming every MP votes.
Sky News analysis suggests that – as it stands – Mr Johnson has a path to gaining about 316 votes, meaning the outcome is on a knife edge.
Speaking in Brussels after EU leaders signed off a deal, the PM was typically optimistic.
Mr Johnson said he was “very confident” MPs would approve the deal, calling on parliamentarians to “come together” and deliver Britain’s exit from the bloc in time for the 31 October deadline.
“We’ve been at this now, as I say, for three-and-a-half years,” the PM said.
“It hasn’t always been an easy experience for the UK. It’s been long, it’s been painful, it’s been divisive.
“And now is the moment for us as a country to come together.
“Now is the moment for our parliamentarians to come together and get this thing done.”
Asked about the DUP’s opposition, Mr Johnson claimed the agreement was a “good deal for every part of the UK, particularly Northern Ireland”.
Pressed by Sky’s political editor Beth Rigby as to whether he was making the same mistake as Mrs May by not getting the DUP on side, the PM repeated his optimistic message and declared: “The opportunity is great, let’s do it.”
But the DUP’s Westminster leader, Nigel Dodds, said Mr Johnson had been “far too eager to get a deal at any cost”.
He said: “The fact of the matter is, if he held his nerve and held out he would, of course, have got better concessions that kept the integrity, both economic and constitutionally, of the United Kingdom.”
The party said the agreement created several economic borders down the Irish Sea, which separated Northern Ireland from the rest of the UK.
In comments that will be seen as putting pressure on MPs to back the PM’s deal, the EU’s Jean-Claude Juncker there was “no need for prolongation” of the Brexit process as there was a deal on the table.
“That’s not only the British view, that’s my view too,” the outgoing European Commission president said.
Another senior EU figure, European Council President Donald Tusk, voiced his “sadness” at the UK’s exit and said “our door will always be open” if it wants to rejoin.
This was echoed by Irish Prime Minister Leo Varadkar, who described the UK as “like an old friend that is going on a journey without us”.
He said there would “always be a place” if it decided to return.
As attention turns back to Westminster, focus will in part turn to the call in some quarters for a second referendum on the deal the PM has struck.
Jeremy Corbyn has said he does not “suspect” the option of holding a vote in parliament on whether to have a referendum would arise on Saturday.
He described reports that his party could back such a move as “high-level speculation on a hypothetical question”.
Meanwhile, the SNP’s Westminster leader Ian Blackford has tabled an amendment to the “appalling” deal, demanding an immediate extension and general election.
If the PM fails, then under the terms of legislation passed by opposition MPs he will have to ask for a delay to Brexit in order to avoid a no-deal exit.
Despite the so-called Benn Act, Mr Johnson has remained adamant that Britain will leave the EU on 31 October.
A senior government source said on Thursday that the PM’s position was “new deal or no deal, but no delay”.