LONDON — For the Brexiteers, it’s stick or twist time.

With members of parliament poised to wrest control of Brexit from the government, senior Conservative Euroskeptics held talks with Theresa May Sunday in a last-ditch bid to resolve the crisis without a full-blown Tory civil war.

After EU leaders last week imposed a new, hard deadline of April 12 — by which time the U.K. must either agree May’s deal, walk away with no deal or ask for a long extension to Article 50 — the choice facing Conservative Brexiteers has quickly crystalized.

They can either stick with the deal to avoid something worse imposed by parliament or gamble everything on no deal, even if this may come only after a long delay and a general election under a new Tory leader. The answer to this question, which will likely be settled in the coming days, could shape British politics for decades to come.

The only thing that appears certain, after a tsunami of devastating headlines Sunday about Tory MPs turning against their leader, is that the prime minister's days now look numbered.

MPs will take their first trepidatious steps along the road to this decision in the House of Commons Monday when they vote on a proposal to take control of the parliamentary timetable from the government.

The move was denounced on Sunday by Brexit Secretary Stephen Barclay on the BBC's Andrew Marr show as "constitutionally unprecedented and a very serious risk to Brexit itself."

An amendment to a motion setting out what the government plans to do next has been put forward by senior Tory backbencher Oliver Letwin creating time on Wednesday for a series of “indicative votes” on alternative Brexit plans to May’s deal.

Should the amendment pass, as expected, it will set the clock ticking for an explosive day in parliament on Wednesday in which a majority might, for the first time, be assembled in favor of one form of Brexit, rather than simply against the prime minister’s.

However, these votes are not binding on the government. Further parliamentary maneuverings will be required, should a majority agree one course of action or another, to turn any proposal into law.

The only hope for the government is that MPs change the equation by legally removing no deal as an option in the short term.

Barclay said the government would decide when to bring back the prime minister’s deal for a third time after Monday’s votes — either before or after the parliamentary fireworks on Wednesday. A crisis Cabinet meeting will be held Monday at 10 a.m., local time, to agree the government’s strategy.

Ahead of that, on Sunday afternoon, the prime minister met with six of her ministers plus seven backbenchers — mostly from the Brexiteer wing of the party — at her Chequers country residence. The attendees included former Foreign Secretary Boris Johnson, former Brexit Secretaries David Davis and Dominic Raab, as well as Jacob Rees-Mogg.

A Downing Street spokesperson said the talks were "lengthy," and covered "a range of issues, including whether there is sufficient support in the Commons to bring back a meaningful vote this week.”

They will also undoubtedly have touched on Letwin's move to hold indicative votes. The consequences of these could be seismic for Britain’s exit from the EU.

First, should MPs seek to legally remove no deal as an option in the short term — by finding a way to force the prime minister to apply for a long extension to Article 50 — the conditions for May’s deal passing become better, though few are convinced even that will be enough to get it over the line.

Former Tory leader Iain Duncan Smith, who has twice voted against the prime minister’s deal, told the BBC Sunday: “I am going to keep — and I recommend my colleagues do — keep their options open on this, because we don’t know what’s happening this week. We have no idea what the alternatives are and whether people vote for this or not depends hugely on whether we are able to leave with no deal or not, or whether there is a change to this.”

However, should parliament agree to take no deal off the table, or an alternative way forward other than the PM’s deal, it appears impossible the Conservative government will be able to implement it, according to Brexit Secretary Barclay.

As May faces up to another make-or-break week, the price many Conservative MPs are now demanding for their support is that she publicly agrees to stand down.

“The vote itself would potentially collide with fundamental commitments the government has given in their manifesto,” Barclay told Marr.

In this scenario, Barclay said, a general election may be necessary to break the impasse.

“Ultimately at its logical conclusion, the risk of a general election increases because you potentially have a situation where parliament is instructing the executive to do something that is counter to what it was elected to do,” he said.

Barclay’s reading was quickly backed by those on the Brexiteer wing of the Conservative Party. Backbencher Simon Clarke said this is the “constitutionally correct position.” He added: “Better that, surely, than our being reduced to the transmission mechanism for policies that are not our own — and which fly in the face of the promises on which we were elected.”

The only hope for the government is that MPs change the equation by legally removing no deal as an option in the short term.

“What would potentially be opened by the process is also whether then parliament would go on to legislate to enforce, for example, taking no deal [off the table],” Barclay said.

However, even this might trigger an immediate election, Barclay said. “The only consequence of that would be European parliamentary elections, and I think for many in the Conservative Party, but in parliament as a whole, that would run directly counter to what people stood [on] in the [2016 general election] manifesto.”

As May faces up to another make-or-break week, the price many Conservative MPs are now demanding for their support is that she publicly agrees to stand down for the next round of the Brexit negotiations.

For others it has already gone too far. May needs to go before any agreement is signed with Brussels. If parliament forces the government to apply for a long delay to Brexit to let that happen, so be it.

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