A call for Brexit to be delayed to give the UK more time for a better deal has provoked a furious bust-up between pro-Remain and pro-Leave MPs.
Leave supporters on a powerful Commons committee have angrily disowned a report calling for the Brexit transition period to be extended if necessary.
The controversial proposal comes in a report by the all-party Brexit Select Committee of MPs on the progress of the UK’s negotiations on EU withdrawal.
The call, led by committee chairman former Labour Cabinet minister Hilary Benn, has been backed by 12 other MPs on the 21-member committee.
But the eight pro-Leave MPs on the committee have denounced their colleagues as “the high priests of Remain” and published their own minority report.
The MPs backing Mr Benn include pro-EU Labour MPs Stephen Kinnock, Emma Reynolds and Pat McFadden, the SNP’s Joanna Cherry and former Tory Cabinet minister Stephen Crabb.
The eight rebels include hardline Tory Eurosceptics Jacob Rees-Mogg, Peter Bone, Sir Christopher Chope, Craig Mackinlay and former Cabinet minister John Whittingdale.
Launching the majority report, Mr Benn said the divisions in the committee showed that achieving an agreement on Brexit was far from easy.
“The Government must now come forward with credible, detailed proposals as to how it can operate a ‘frictionless border’ between Northern Ireland and the Republic of Ireland,” he said.
“At the moment, the committee is not persuaded that this can be done at the same time as the UK is leaving the single market and the customs union.
“We know of no international border, other than the internal borders of the EU, that operates without checks and physical infrastructure. This is deeply concerning.”
Mr Benn said that in the past few days Brexit Secretary David Davis had said he could live with a transition period of under two years if it helped to secure an early deal.
And he added: “But even this time could prove to be too short to conclude a comprehensive agreement. Given the modelling we have seen, a ‘no deal’ scenario is a significant danger to the UK.”
But Mr Rees-Mogg, chairman of the Brexit-supporting Tory European Research Group, said: “The committee’s majority report is the prospectus for the vassal state.
“It is a future not worthy of us as a country, and I am sure that Theresa May will rightly reject a report by the high priests of Remain.
“The majority report would keep us in the customs union and the single market, which is an attempt to keep us in the EU by sleight of hand.
“Those of us who respect the instructions the people gave us in the referendum could not support so partisan a text.”
The minority report says 21 months is ample time and that a prolonged transition period would be difficult for the UK and would not respect the EU referendum result.
It says the UK would still be bound by EU rules and would have to hand over cash with no say on how it was spent if the implementation arrangements were extended.
Mr Whittingdale, vice chairman of the Brexit committee, said: “I am very disappointed that the committee was unable to produce a unanimous report and instead divided along the same lines as in the referendum campaign.
“For a number of us the chairman’s report was far too negative and we do not believe that its conclusions are borne out by the evidence we heard.
“The report’s recommendations essentially ignore the wishes of the people and would delay Brexit by an indefinite period.”
Reacting to the committee split, Mr Davis’s Brexit department said a “great deal of progress” had been made on citizens’ rights, a financial settlement and the Northern Ireland border.
“Importantly, the UK and the EU are equally committed to ensuring that our departure does not lead to a hard border between Northern Ireland and Ireland,” a spokesman added.
“We are currently discussing the terms of an implementation period and are confident we can reach an agreement by the European Council next week.
“Doing so will provide businesses and citizens with the certainty they need as we prepare for exit.
“It remains a shared aim to get the withdrawal agreement agreed by October and we will continue to work closely with the commission to achieve that.”