Conservative ministers and MPs expect Theresa May to fight on as prime minister until later this year.

Angry pro-Brexit MPs are trying to force her out in the next few weeks.

But there is a growing belief that she will refuse to quit until MPs vote for a Brexit withdrawal deal, meaning she could remain in post until the end of the year.

Conservative politicians and activists are bracing themselves for brutal local and European election results.

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LONDON — Theresa May will resist growing calls for her to stand down, despite the increasingly furious reaction towards her decision to delay Brexit, Conservative Members of Parliament now believe.

The prime minister this week triggered huge anger among pro-Brexit MPs in her party when she agreed to delay the United Kingdom's exit from the European Union by six months to October 31.

Prominent pro-Leave MP Bill Cash on Thursday used a House of Commons question to call on her to resign over her "abject surrender" on Brexit.

Meanwhile, members of the European Research Group of pro-Brexit Tories wrote to party authorities on Monday demanding a vote of no confidence in her leadership.

However, since May's trip to Brussels where she agreed the Brexit delay, Conservative MPs and members of her government have told Business Insider they expect her to resist moves against her and stay on until the end of summer.

She is a limpet and I don't think she will stand down...

"She is a limpet and I don't think she will stand down until her deal goes through," one government minister told Business Insider.

"Her tactic will now be [tell MPs] to go off and come back with abuse ringing in your ears and support my deal."

Two senior MPs and former ministers agreed, telling Business Insider that she will remain as prime minister until MPs vote for a Brexit deal, which could be as late as October and after the Tory party's autumn conference.

"I think there is an off chance that if she amends the Political Declaration she could hold onto 225 Tories and add enough to get the deal through," the minister said.

The prime minister last month told her party that she will quit as soon as the House of Commons backs a Brexit deal.

A Downing Street source reiterated this position during May's trip to this week's crunch European Council summit.

"She understands that the Conservative Party feels a sense that new leadership is required for the second phase of negotiations," they said.

"That was the commitment she gave to her parliamentary colleagues and that's one she stands by."

Chancellor Philip Hammond on Friday told Bloomberg that May could fight on until the end of October.

"As far I know she doesn’t have any intention of leaving until that deal is done," he said.

Clinging on

The prime minister's decision to extend the Article 50 withdrawal process until the end of October means that she could remain in post for another six months or more.

There is a widespread belief among Tories that she will come under huge pressure to stand down in the next few weeks amid fears that the party will lose swathes of seats at the local and European elections.

One Conservative Member of the European Parliament predicted that the party would be wiped out in his region.

Our vote could completely collapse... We will get absolutely hammered.

"Our vote could completely collapse... We will get absolutely hammered," they told BI this week, adding that the party will go into "meltdown" if next month's elections go as badly as they and others predict.

A poll published this week indicated that Labour would receive 38% of the UK vote at next month's European elections. This would be an increase of 14% and lead to Conservative MEPs being ousted nationwide.

One source close to a leading Brexiteer in May's Cabinet told Business Insider that they still believed May would be gone sooner rather than later, despite the prime minister's best efforts to overcome the critics.

They said they expected the prime minister to be forced out by the end of next month, paving the way for a summer leadership contest to choose her successor.