Boris Johnson’s promise to deliver a “real Brexit” on October 31 was facing a parliamentary ambush by Conservative grandees on Saturday, with Downing Street fearing it could be heading for defeat in a critical vote.
Oliver Letwin, a former Tory cabinet minister, tabled an amendment to the Act of Parliament that would approve Mr Johnson’s new Brexit deal, signed off by EU leaders in Brussels earlier this week.
Officials said the amendment by Sir Oliver would have the effect of withholding formal parliamentary approval for the deal. MPs would not formally approve the Brexit deal in a so-called meaningful vote until the implementation of legislation — known as the Withdrawal Agreement bill — had passed all its parliamentary stages.
The aim would be to allow greater scrutiny of the legislation — and enable MPs to amend Mr Johnson’s Brexit plan — and to stop the prime minister taking Britain out of the EU without a deal on October 31 if he did not agree with the way the bill had been amended.
The move came as hundreds of thousands of people were expected to march through London and gather outside parliament on Saturday to demand that voters were given a final say on Brexit through a second referendum.
Mr Johnson’s allies admitted Sir Oliver, backed by Labour, former Tory cabinet ministers and opposition parties, could win a majority for the move, halting the prime minister’s drive to push quickly ahead to ratify the deal and take the UK out of the EU by Halloween.
If MPs back the amendment, Mr Johnson’s allies said the effect would be to postpone the long-waited Commons vote on the new deal and that Tory MPs would be sent home early on Saturday afternoon.
Instead, Mr Johnson would bring forward the Withdrawal Agreement bill to implement the Brexit deal for a Commons second reading vote on Tuesday — meaning that vote would become the “crunch” decision for MPs.
The prime minister, opening the first Saturday sitting of the House of Commons since the Falklands War in 1982, urged MPs to reject the Letwin amendment and to deliver on the public’s desire to “get Brexit done”.
“This deal provides a way forward,” he said. “It is a new and better deal for the UK and for our friends in the EU.”
But the frustration in Downing Street at Sir Oliver’s move was palpable. “We are edging towards getting a majority for the deal,” said one Tory insider. “The Letwin amendment just complicates everything.”