Theresa May will be obliged to present MPs with a new Brexit plan within three days if her current proposal is voted down next week, after a procedural amendment to the plan’s progress through the Commons was passed amid chaotic scenes.
The amendment to the business motion for the plan, drawn up by the Conservative former attorney general Dominic Grieve, gives May the deadline to put forward new her plans if she loses the vote, as many expect, next Tuesday.
The amendment was passed by 308 votes to 297 following stormy scenes which saw a series of Conservative MPs castigate the Speaker, John Bercow, for allowing the amendment.
Tory MP Ken Clarke, who backed the amendment, said those who did not like the amendment should “don a yellow jacket and go outside” to join some of the hard-right protesters who had harassed MPs outside parliament.
The amendment says that if the deal is defeated “a minister of the crown shall table within three sitting days a motion … considering the process of exiting the European Union under article 50”.
Earlier Grieve said the change was sensible given the time pressures. “I realise there are a few of my colleagues who believe that if the government’s deal is rejected we should simply do nothing and leave the EU on March 29 with no deal at all and with all, to my mind, the calamitous consequences that would follow on from it,” he told the BBC.
“I disagree with that, and so I think do the vast majority of members of parliament. The only way we can move forward if the government’s deal is not acceptable to parliament is for parliament to engage with government and find a solution, which is what I am trying to do.”
Other MPs who signed the amendment include the former Tory cabinet minister Sir Oliver Letwin and ex-Tory ministers Jo Johnson, Guto Bebb and Sam Gyimah. It has also been backed by Labour MPs including Stephen Doughty and Chris Leslie.
The government is now faced with returning with an alternative plan within three days, instead of the 21 days it had previously been given as part of the EU Withdrawal Act.
That statement can in itself be amended by MPs because of a previous amendment by Grieve voted through by the Commons before Christmas. That will allow MPs to put forward their own alternatives for the future of the Brexit process.
The latest blow for May comes a day after the government suffered a significant defeat on the finance bill, in which a powerful cross-party group of MPs led by Labour’s Yvette Cooper passed an amendment limiting the government’s tax administration powers in the event of the UK leaving the EU with no deal.