A Tory split erupted last night over Boris Johnson's Brexit deal before the Prime Minister has even got it from the EU.
Hardline Brexiteers revealed a divide - which could scupper any hope of passing a deal in Parliament this Saturday - after being invited in for crucial talks in 10 Downing Street.
Tory MPs and Boris Johnson's DUP allies were briefed as Brussels talks go down to the wire ahead of an EU summit tomorrow.
But while many showed support for an emerging deal, prominent Tory Owen Paterson blasted the reported plan as "absurd and unacceptable".
Mr Paterson hit out at reports that the EU is considering a customs border down the Irish Sea - contrary to what Boris Johnson suggested two weeks ago.
He told The Sun: "Concerns remain that the EU will seek to trap Northern Ireland permanently in the EU Customs Union by trying to reheat the failed ideas of customs partnerships or single customs territories that proved so disastrous for Theresa May ."
He added: “When would any other country ever give up part of its territory as part of trade talks? It would be particularly absurd for Northern Ireland.
“It would shatter the Belfast Agreement’s Principle of Consent and completely undermine Northern Ireland’s status as an integral part of the UK. We must not go down this route."
Mr Paterson spoke out despite other hardline Brexiteers offering Mr Johnson support.
Self-styled " Brexit hardman" Steve Baker later said he was "optimistic" that Mr Johnson's team would finalise a "tolerable deal that I will be able to vote for".
And Jacob Rees-Mogg , the Commons leader who sits in the Cabinet, told LBC "I think the votes are there now for a deal" in Parliament.
But the DUP were lukewarm despite a 90-minute meeting between their leader Arlene Foster and the PM last night.
"Gaps remain and further work is required," a spokesman said after Ms Foster slipped out the back gate of No10 to avoid the press.
Today Iain Duncan Smith, a former Cabinet minister, denied he "exploded" at No10 officials over the planned deal saying "I wasn't exploding anywhere".
Mr Duncan Smith added he and other Tories were not shown details of the deal.
But he admitted a possible split, telling BBC breakfast: "People often talk about the [Brexiteer group] ERG as some sort of homogeneous group. It's not.
"People make their own minds up and they will meet no doubt to discuss that in the next few days."
And he said there was no need for a "technical" extension to the Brexit date - a prospect one minister, Oliver Dowden, repeatedly refused to rule out today.
Mr Duncan Smith said there could be "some accommodation" but added: "Clearly it's important that the sovereign status of the UK remains exactly that - sovereign.
"It's not for other countries to dictate where our borders lie and how they work."
