David Davis quitting as Brexit secretary would be 'deeply dangerous for the country', former Tory minister warns Theresa May

Brexit secretary rumoured to be considering resigning amid tensions with prime minister over customs backstop

Theresa May has been warned losing David Davis would "deeply dangerous" amid reports the Brexit secretary is considering resigning.

In a sign of growing concern among Tory Eurosceptics over Downing Street’s Brexit plans, David Jones, a former Brexit minister, told the prime minister she must keep Mr Davis on side.

If comes ahead of a crunch meeting of the Brexit war cabinet, with Mr May and Mr Davis set for a showdown over plans for a customs “backstop”.

Reports suggest the Brexit secretary is considering resigning if the proposal is published without his approval. He has refused to deny the speculation, saying the question of whether he kept his job was a matter for the prime minister.

Mr Jones warned Ms May that Mr Davis "needs to stay where he is".

He told the BBC Radio 4's Today: "I don't think David Davis should resign. He's been outstandingly good at his job...he would be a huge loss to the government and I don't think we should contemplate that scenario.

"We need to make sure that David Davis stays at the negotiating table. Anything that caused him to leave would be deeply regrettable and deeply damaging to the country."

"I would be deeply upset if David Davis were no longer the Brexit secretary."

He added: "To contemplate these negotiations continuing without David Davis would be deeply upsetting and deeply dangerous for the country. David Davis needs to stay where he is."

The "backstop" proposal is designed as a fall-back solution if no other arrangement is reached for avoiding a hard border in Northern Ireland, but the cabinet is divided over whether it should include a specific time limit.

Brexiteers, led by Mr Davis, want a legally-binding, clear limit but Downing Street. The current proposal is understood to pledge the arrangement would be temporary but not include a specific cut-off. No 10 believes a strict time limit means the plan would be dismissed by the EU.

Mr Jones warned the prime minister the current proposal was "unacceptable"

"An arrangement whereby we're indefinitely tied to EU customs arrangements, which means that we won't be able to have our independent trade policy, which means we'll be tied effectively to European Court of Justice jurisdiction, would just not be acceptable, I think, to the mass of the Conservative Party."

He added: "If that is what is proposed it's going to cause an awful lot of problems within the parliamentary party."

Speaking at the Royal United Services Institute (RUSI) on Wednesday, Mr Davis refused to rule out the possibility of resigning.

Asked if he would be able to stay in his job if the backstop proposal was published without his approval, the Brexit secretary said: “That’s a question, I think, for the prime minister, to be honest.”

He also confirmed the plan was yet to agreed by ministers, saying: “The detail of this is being discussed at the moment. it’s been through one cabinet committee, it’s going to another and it would be improper of me to pre-empt the negotiations there, but I suspect it will be fairly decisive.”