The Conservatives will be stuck with Theresa May as leader for the next general election unless they move to get rid of her now, ardent Brexiteer Jacob Rees-Mogg has warned his party.

Amid signs the attempt by Tory rebels to force a vote of confidence in the Prime Minister has stalled, the Somerset MP acknowledged they were struggling to get the support they needed.

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However, Mr Rees-Mogg, who leads the pro-Brexit European Research Group [ERG] insisted there was little enthusiasm among Tory MPs for Mrs May to take them into the next election, due in 2022.

"It is now or the Prime Minister will lead the Conservatives into the next election," he told reporters at a Westminster news conference.

Last week, senior ERG figures were confidently predicting they would get the 48 letters of no-confidence from MPs needed to trigger a vote in Mrs May's leadership.

But with Brexiteers apparently divided over whether it was the right time to mount a challenge, the prospect of them achieving their target appeared to be dwindling.

Yet Mr Rees-Mogg warned that they needed to consider whether they really wanted to carry on with her at the helm.

While party rules would permit a fresh challenge in a year's time if there were a failed attempt now, he said that in practice it was doubtful that would happen.

"Basically, if there is a vote of confidence it is not just for a year. Getting the 48 letters has shown to be quite difficult, so the idea that in a year you just repeat the process and then she would go at that point, I don't think that is realistic," explained the Tory backbencher.

Asked if his attempt to unseat the Prime Minister had been exposed as a "Dad's Army" operation, Mr Rees-Mogg replied: "I've always admired Captain Mainwaring."

Senior ministers sought to rally round Mrs May, with David Gauke, the Justice Secretary, warning that any move to oust her would be "dangerous for the country".

He told BBC Breakfast: "The idea that at this point, in the middle of a very delicate negotiation, that is hugely important to the future of this country, that we should remove the Prime Minister, essentially leave us leaderless, for certainly several weeks, possibly months, would be hugely irresponsible.

"I don't think people should be talking about removing her at this point. I think that would be self-indulgent and dangerous for the country."

The latest threat to Mrs May followed a shot across the bows from the DUP, who prop up her minority Government in the Commons.

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On Monday night the party joined Labour in voting against the Government on a Budget measure while abstaining in two other divisions in apparent breach of their "confidence and supply" agreement.

The party's Brexit spokesman Sammy Wilson said the move was intended to send a "political message" to the Prime Minister after she breached a "fundamental" assurance that Northern Ireland would not be separated constitutionally or economically from the rest of the UK.

"We had to do something to show our displeasure," he told the BBC.

In another cause for concern for the PM, Mrs May's Spanish counterpart Pedro Sanchez said Madrid would vote against the withdrawal deal at the summit on Sunday if Gibraltar's future was not considered a bilateral issue between the UK and Spain.

In a bid to sway opinion, Mrs May has insisted that her draft Brexit deal put Northern Ireland in a "fantastic position" for the future.

In an opinion piece published in the Belfast Telegraph, she claimed the region's constitutional status within the UK had been guaranteed in the agreement.

The PM acknowledged that there had been a lot of focus on the Irish border "backstop" and said she "understood and share some of the concerns that have been expressed". But she added the backstop was an "acceptable insurance policy" due to provisions in the deal.