THREE Cabinet ministers have issued a stark warning to Theresa May, signalling that they are prepared to resign if she does not halt Brexit in its tracks to stop a “disastrous” no-deal outcome.

Amber Rudd, the Work and Pensions Secretary, Greg Clark, the Business Secretary, and David Gauke, the Justice Secretary, have made clear they are ready to openly defy the Prime Minister if there is no breakthrough on her deal next week.

The three Cabinet ministers along with David Mundell, the Scottish Secretary, met Mrs May on Monday to talk through their concerns. The Herald understands Mr Mundell will not threaten resignation and would only leave the Government if a no-deal Brexit actually happened.

Writing a joint article in The Daily Mail, the three senior ministers make clear that if the Tory Brexiteers of the European Research Group[ERG] are able to block a deal, then they will back other MPs to try to force the PM to extend Article 50 and delay Britain’s exit from the EU. This would be against current Government policy.

The frontbenchers warn a no-deal outcome would wreck the economy, jeopardise the defence of the realm and risk the break-up of Britain.

They stress it is still their hope that the Commons can agree a deal “in the next few days”.

But they then add: “If there is no breakthrough in the coming week, the balance of opinion in Parliament is clear: that it would be better to seek to extend Article 50 and delay our date of departure rather than crash out of the European Union on March 29.

“It is time that many of our Conservative parliamentary colleagues in the ERG recognised that Parliament will stop a disastrous no-deal Brexit on March 29. If that happens, they will have no one to blame but themselves for delaying Brexit.”

On Wednesday, MPs will take part in a crunch vote. Among the tabled options will be to extend Article 50 to enable the Government more time to agree a deal with Brussels, have a People’s Vote with the option to remain or pass the PM’s deal but then have a confirmatory referendum.

Whitehall appears resigned to Mrs May not being able to bring back a fresh deal by Wednesday. She will be in Egypt for an EU-Arab summit on Sunday when she is expected to have talks with Angela Merkel, the German Chancellor, and Donald Tusk, the European Council President.

But no one is now expecting an imminent breakthrough, thus pushing the process through to March with the prospect of matters going to the wire before exit day on March 29.

However, the trio of ministers’ threat means that, to keep her Cabinet intact, the PM will have herself to seek a delay to Brexit, something which she has hitherto strongly opposed.

Conservative backbencher Phillip Lee, a leading supporter of the People’s Vote campaign, said: “For too long a dangerous game of brinkmanship has been played with the prospect of a no-deal Brexit. It is hugely encouraging that Conservative ministers who care deeply about the national interest are now ready to draw a line under this recklessness.

"If a no-deal Brexit is ruled out, we can then have a rational debate about whether the proposed deal is one that meets the promises of the last referendum, is as good as that we already have inside the EU, or offers us the clarity needed to invest and build for the future.

“The time is coming when all MPs will have to decide whether they want to impose that on the British public without asking them first. The time is coming when all this will have to be put to the people,” he added.