Senior Brexiteers are split over whether to oppose Rishi Sunak’s deal with the European Union on Northern Ireland.
The prime minister has won a key battle in his fight to convince his party by securing the support of influential eurosceptics.
Hardline Brexiteers have warned that up to 100 Tory MPs could oppose the new post-Brexit trading arrangements in a potential vote amid warnings of a potential Tory “civil war”.
But the prime minister is understood to have convinced prominent pro-Brexit MPs of the merits of his deal with Brussels.
One senior Brexiteer praised the proposed agreement between London and Brussels as “very good”, although he warned that parts of the way it had been handled risked “snatching defeat from the jaws of victory” after a row over King Charles’s cancelled meeting with European Commission president Ursula von der Leyen.
Mr Sunak does not have to offer MPs a vote on the deal and has carefully avoided publicly committing to one. But members of the European Research Group of Eurosceptic Tory MP have told The Independent they are prepared to force a showdown vote in parliament.
But the senior Brexiteer said that his advice to the government “has been to avoid a vote if you possibly can”.
The split means the prime minister could be poised to push through a historic deal resetting the UK’s post-Brexit relationship with the EU. Mr Sunak could either win a Commons vote with Labour support, although that would still be hugely controversial within his party, or dodge a vote and face a smaller-than-expected Tory backlash.
On Saturday, a buoyant Mr Sunak took on the hardliners in his party saying his deal, close to being agreed upon with the EU, would finally “get the job done” on Brexit.
In a message to MPs in his own party, he said the new agreement would not be a threat to Brexit but is about “making sure that Brexit works in every part of the United Kingdom”.
“As someone who believes in Brexit, voted for Brexit, campaigned for Brexit, I want to demonstrate that Brexit works and it works for every part of the United Kingdom,” he told The Sunday Times.
“There’s unfinished business on Brexit and I want to get the job done.”
He also warned sceptics to ensure Northern Ireland’s peace process was “uppermost in their minds”.
A senior member of the ERG told The Independent the deal would have to secure the support of the DUP: “We have traditionally been allies of the DUP and the blunt truth is, if they reject this deal, then it won’t land anyway. It is vital to uphold the Good Friday Agreement, which means retaining Unionist support – and that means convincing the DUP; without them, nothing will work.”
On Saturday, DUP sources said their message to the government remained that it was more important to get the deal right rather than have it rushed.
But Tory MPs have been told to be in parliament on Monday as expectation over a possible deal builds.
Political parties in Northern Ireland were on standby for the prime minister to fly in over the weekend if a deal is agreed, though it is understood a number of them have been cautioning that such a move could prove counterproductive. The prime minister has also been told to “stand firm and see this through” ahead of the expected clash with Brexiteers.
Former minister and chair of the Commons defence select committee, Tobias Ellwood, said: “All parties should be supporting what’s best for the NI and GB economies – not pursuing a dated agenda framed by opinion in 2016 which is now at odds with what in 2023.
“I encourage the PM to stand firm and see this through.”
He said the UK was “increasingly bewildered by the blue on blue (row which) prevents common sense and compromise from prevailing”.
Last week, former prime minister Boris Johnson sparked a furious outcry when he backed a Bill which would unilaterally scrap part of the current Brexit deal. Mr Sunak is understood to be willing to park the Bill in the Lords in return for a new agreement with Brussels. But the issue threatens a cabinet split after home secretary Suella Braverman urged the prime minister not to ditch the Bill this week.
Some ministers are also on resignation watch amid fears they may quit over the deal itself. Under the proposed agreement, it is thought almost all EU checks on goods crossing between Britain and Northern Ireland would be scrapped. But the DUP is unhappy it could still leave some EU legislation applied to goods made in Northern Ireland.
They have long protested against the current arrangements, warning they put a border down the Irish Sea, effectively separating Northern Ireland from the rest of the UK. But they say any new deal would have to meet seven key tests before they can accept it and re-enter power sharing in the government of Northern Ireland, which is currently in abeyance.