THERESA May’s Cabinet colleagues have been urged by Jeremy Corbyn to rebel to stop a no-deal outcome as the Labour leader accused the Prime Minister of “playing chicken” with people’s livelihoods.

And in a move that her critics believe is more proof of Mrs May “running down the clock” to Brexit day, she announced that a law allowing for 21 days of parliamentary debate following a treaty change would be disapplied to enable necessary legislation to be passed before March 29.

In a Commons statement, the PM called on MPs to "hold their nerve" and come together behind an EU withdrawal deal which would deliver Brexit on schedule in 45 days’ time.

Addressing the House a fortnight after MPs voted for her to go back to Brussels and replace the controversial Irish border backstop, Mrs May acknowledged that she would need "some time" to hold talks with the EU.

She said that a planned Commons debate on Thursday would be on an amendable motion reaffirming the House's decision on January 29 that it supported the Government's efforts to find an alternative for the backstop and recognising that talks are ongoing.

Mrs May also pledged to return to Parliament on February 26, if no deal had been secured with Brussels before that time, to report back on progress and trigger a further MPs' vote the following day.

"We now all need to hold our nerve to get the changes this House requires and deliver Brexit on time," she declared.

"By getting the changes we need to the backstop, by protecting and enhancing workers' rights and environmental protections and by enhancing the role of Parliament in the next phase of negotiations, I believe we can reach a deal that this House can support.

"We can deliver for the people and the communities that voted for change two-and-a-half years ago and whose voices for too long have not been heard; we can honour the result of the referendum.

"And we can set this country on course for the bright future that every part of this United Kingdom deserves; that is this Government's mission. We shall not stint in our efforts to fulfil it," she added.

But Mr Corbyn accused the PM of running down the clock so that MPs would be "blackmailed" by the fear of a no-deal Brexit into supporting her “deeply flawed deal".

"This is an irresponsible act," declared the Labour leader. "She is playing for time and playing with people's jobs, our economic security and the future of our industry."

Mr Corbyn accused Mrs May of refusing to listen to his alternative deal, involving permanent customs union membership, a close alignment with the single market and matching EU workplace and environmental protections.

By Thursday, Labour is expected to table an amendment to try to force the PM to hold a second “meaningful vote” on her Plan B this month. It is not expected to succeed without Conservative help.

Already, some Cabinet ministers have expressed serious unease about the prospect of a no-deal outcome and have even hinted at resignation.

The Leader of the Opposition made a direct appeal to them as they sat on the Government frontbench. He said: “No minister, serious about protecting jobs in this country, would allow a prime minister to deliberately run down the clock and play chicken with people's livelihoods. To stand by and do nothing would be a complete dereliction of duty."

He added: "Now is not the time to stand idly by, now is the time to stand up and do the right thing: to rule out no-deal and back Labour's alternative plan."

In a new development, Mrs May informed MPs that the Government would move to disapply a provision in the 2010 Constitutional Reform and Governance Act, which stipulates there has to be 21 days between a treaty being signed and it coming into force to enable Parliament to debate it.

In response to a point raised by the leading Conservative Remainer Dominic Grieve - who warned time was so short that even if she got her deal through the PM would have to extend the Article 50 process - Mrs May explained that the 21 days stipulation was important to enable MPs to debate details they had not done so before but noted in the case of Brexit they already would have.

“While we will follow normal procedure if we can, where there is insufficient time remaining following a successful meaningful vote, we will make provision in the Withdrawal Agreement Bill – with Parliament’s consent – to ensure we are able to ratify on time to guarantee our exit in an orderly way.”

Labour’s Luciana Berger, noting how the PM did “not intend to honour” the 21 days’ stipulation, said any newly agreed agreement would deal with thorny issues such as the divorce bill, EU citizens’ rights and supremacy of EU law during the transition period.

“How on earth does the PM expect members on all sides of this House to consent to that legislation without seeing a draft at this moment in time? Will she not acknowledge there is no chance that she is going to pass that legislation in 45 days’ time?”

The Liverpool MP added: “On that basis, will she commit to extending Article 50 so that this country does not crash out with no-deal, threatening jobs up and down this country?”

Mrs May repeated the 21 days’ hiatus was there because MPs would not normally have seen the details of a proposed treaty but in this case they had already done so.

“We are looking for changes in the agreement but the vast majority of it would not be changed in the discussions we are having with the EU and the House has already been able to look at that as part of the meaningful vote.

“I’m sure when a meaningful vote has been agreed in this House, then every member would want to ensure they are able to operate on a timetable that enables us to leave at the end of the two-year period agreed by this House when we triggered Article 50,” she added.