MPs have warned Theresa May that parliament is ready to seize control of Brexit and push for a softer version if her deal fails to get through the House of Commons.
Groups of MPs are preparing to test their versions of Brexit via a series of amendments if it is clear May’s deal is doomed.
A senior cabinet source said the government had not ruled out holding indicative votes in the Commons to determine appetite for different Brexit options if there was a large defeat on Tuesday.
#Labour’s Yvette Cooper, one of the key players behind parliamentary moves to stop no deal, has said she and a cross-party group of MPs would consider steps to force those indicative votes as an amendment to any motion for an extension to article 50.
That motion for extension is likely to be laid by the government on Thursday, a vote May has promised should her deal fail to pass on Tuesday and if parliament then votes against no deal on Wednesday.
Options for indicative votes could include a customs union, a full EEA-style deal including membership of the single market, a second referendum, and others that MPs could table.
Labour MPs pressing for a “common market 2.0” kind of Brexit said they were conducting intensive shuttle diplomacy between Jeremy Corbyn’s team and Conservative MPs who might be ready to back the idea.
Intensive discussions led by the Labour MPs Stephen Kinnock and Lucy Powell are under way over the wording of a potential backbench amendment that might be close enough to Labour’s version of Brexit to allow the leadership to support it.
Corbyn met the Conservative former ministers Nick Boles and Oliver Letwin last week for an hour-long discussion that both sides described as productive. However, the idea that a Labour Brexit is still in play is likely to infuriate those Labour members who think the party’s priority should be pushing for a referendum.
Kinnock said his group would not table an amendment to the meaningful vote this week, but was still hoping to find a form of words that the Labour frontbench could support. “We will not fire our bullet this week,” he said. “We will keep our powder dry.”
He and his colleagues insist there is a “silent majority” for a softer form of Brexit, with up to 50 Conservative MPs prepared to back the idea rather than countenance no deal.
If May loses her vote on Tuesday or does not find some other way to swerve the sequence, MPs are expected to vote this week to reject a no-deal Brexit and to extend article 50.
Kinnock and his allies believe a short extension, of three months, would be sufficient to allow a common market-style agreement to be negotiated. “We’re at five minutes to midnight, so it’s got to be an off-the-shelf model,” he said.
By contrast, they argue that a second referendum, preferred by many Labour MPs, would take much longer to arrange. That would extend the process beyond the deadline for choosing a new batch of MEPs in the European elections.
Robert Halfon, one of the Conservative MPs behind the common market 2.0 plan, said he was “very excited by it” but added that there was more work to be done around getting agreement on a type of customs arrangement, which many Conservatives would not want to be a permanent customs union.
Cooper had said she and Conservative MPs would attempt to force votes on an extension of article 50 on Thursday should the prime minister pull the votes, saying it would be a “straight-up lie” to parliament if May changed her plans.