Conservative MPs implacably opposed to a no-deal Brexit will try to amend government legislation as early as next week as a way of binding the hands of Boris Johnson.

A cross-party group is planning another attempt to stop a no-deal Brexit after becoming increasingly alarmed at the tone of Johnson’s pledges to take Britain out of the European Union on 31 October, “do or die”.

They are planning with Labour and other opposition parties to pass an amendment that would rule out leaving without a deal – or at least offer MPs the opportunity of a vote before that happened.

Under one plan, they will try to change the parliamentary estimates bill that comes before the House of Commons as early as next Tuesday, with an amendment to prevent a no-deal Brexit put down in the names of Tory MP Dominic Grieve and Labour MP Margaret Beckett. It would stop the government being able to consume resources and spend cash if it pursued a no-deal Brexit policy.

Another is the possibility of amending some likely emergency government legislation on Northern Ireland power-sharing, which may appear on Wednesday.

The Guardian understands the government is considering introducing an emergency bill next week, to extend the powers civil servants have effectively to govern in Northern Ireland, while the power-sharing assembly continues to be suspended.

Parliamentarians who have discussed the plan are concerned about whether an anti no-deal amendment would be ruled outside the scope of the legislation – but hope they will be aided by the willingness of the Speaker, John Bercow, to bend the rules. However, it is not yet certain to be brought forward.

Bercow said in a speech in Washington last month: “The idea that parliament is going to … be evacuated from the centre-stage of the debate on Brexit is unimaginable. It is simply unimaginable.”

Labour narrowly failed in a recent bid to commandeer the parliamentary timetable for a day, to pave the way for a bid to stop a no-deal Brexit. But a plan led by Conservative backbenchers might have more hope of securing the support of Tory rebels, than one initiated by Jeremy Corbyn and the other opposition leaders.

Passing an amendment would also be a less drastic option than voting to bring down the government.

Several Conservative MPs, including Ken Clarke and Grieve, have said publicly in recent days that they would consider supporting Labour in a motion of no confidence against the government, if they believed a no-deal Brexit was imminent.

Their fears have been raised by increasingly hard Brexit rhetoric from Johnson, who has the backing of key figures in the European Research Group (ERG), which is urging him to deliver Brexit by Halloween, even if that means leaving without a deal.

Corbyn has not ruled out tabling a no-confidence vote in the narrow window between the new prime minister being appointed, on Wednesday 24 July, and the House of Commons rising for its summer recess the next day.

The Labour leader’s spokesman said on Wednesday they would table such a motion when they believe it has the most chance of success.

Supporting Labour in bringing down the government would be a dramatic decision for Conservative MPs, however, who would thereby effectively be resigning from their party.

Under the Fixed-Term Parliament Act, if the government loses a formal motion of no confidence, there is then a fortnight-long period in which alternative candidates can try to assemble a governing majority.

If they fail to do so, a general election is triggered. Liberal Democrat leadership candidate Ed Davey has suggested a government of national unity could emerge in those 14 days, perhaps led by a Labour backbencher such as Yvette Cooper or Hilary Benn.

Philip Lee, a backbench Conservative MP, told the BBC’s World at One that pro-European Conservatives like himself had to be as “ruthless” as the ERG as they seek to stop a no-deal Brexit, which was why they had to keep open the option of voting against the government on a no confidence motion to prevent a no-deal Brexit.

“Nobody wants to vote no confidence in the government, nobody seeks to do that … but ultimately if we believe truly that no-deal is unacceptable without the explicit consent of the public, then we have to leave everything on the table,” he said.

“I’ve watched as the ERG have essentially won through here, and have dictated terms, and they have done this, successfully I might add, by being ruthless and having a clear strategy throughout.

“And it’s about time those of us who hold the belief that a no-deal on these terms is an unacceptable thing to be contemplating that we also adopt exactly the same approach that the ERG have successfully undertaken in the last 12 months.”