THERESA May’s faltering premiership is all but over.

Tory MPs have run out of patience with the Prime Minister – who had already promised to set out a timetable for her departure after the crunch vote on her Withdrawal Agreement Bill – after she opened the door to the possibility of a second EU referendum.

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May’s time in office can now likely be measured in hours rather than days. Late last night, on the eve of the European elections, Andrea Leadsom, the Leader of the House of Commons, became the 36th minister to quit May’s government.

In her resignation letter she urged the Prime Minister to make the “right decisions in the interests of the country, this government and our party”.

May’s decision to give MPs a vote on having a new Brexit referendum was one of the proposals put forward by the Prime Minister in her “bold” new deal.

The Tory leader said MPs would be given a vote on having that referendum if they backed her Withdrawal Agreement Bill when it comes to the Commons early next month.

Even just the prospect of there being a so-called People’s Vote infuriated formerly loyal MPs.

David Mundell demanded a meeting with the Prime Minister, with a source saying he was worried the proposal would be “exploited” by the SNP. However, May cancelled that meeting 10 minutes before it was due to begin.

Jeremy Hunt and Sajid Javid had also asked to talk to the Prime Minister. Both were told no.

The chaos does not bode well for the party’s election prospects. One poll even predicted the Tories UK-wide would only manage to win fifth place today, behind the Greens.

At one point yesterday it seemed as if May had finally buckled under the pressure and was on the brink of resigning, but Downing Street insisted she was going nowhere, and that her Withdrawal Agreement Bill will, as planned, be published tomorrow and go before MPs in the week beginning June 3.

In her resignation letter, Leadsom, one of the most influential Brexiteers in Parliament, said she could not stay in the Government as a second referendum “would be dangerously divisive”.

The National: Andrea Leadsom quit her Cabinet positionAndrea Leadsom quit her Cabinet position

“I do not support the Government willingly facilitating such a concession,” she said. “It would also risk undermining our union which is something I passionately want to see strengthened.”

Leadsom also said “a breakdown of government processes” meant that “recent Brexit-related legislative proposals have not been properly scrutinised or approved by Cabinet members”.

Last night, the executive members of the 1922 Committee of backbench Tory MPs met to discuss a possible change to the party’s no-confidence process to allow a fresh bid to oust May.

Under the existing rules, as she survived a challenge late last year, May is safe until December.

Graham Brady, who is the chair of the committee, is due to meet with the Prime Minister tomorrow.

It is not clear what will happen at the meeting, and the result of today’s vote will not be known until Sunday night when England, Wales and Northern Ireland reveal their new MEPs.

However, it is believed Brady will tell the Prime Minister she can either resign now and leave with some dignity or find herself being removed from Number 10.

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What little authority May had remaining has now all but ebbed away.

Brexit-supporting colleagues did not even bother turning up to Prime Minister’s Questions yesterday.

In the Commons, May appeared to acknowledge that her premiership was drawing to a close.

“In time, another prime minister will be standing at this despatch box,” she told MPs.

“But while I am here, I have a duty to be clear with the House about the facts.

“If we are going to deliver Brexit in this Parliament, we are going to have to pass a Withdrawal Agreement Bill.

“And we will not do so without holding votes on the issues that have divided us the most – that includes votes on customs arrangements and on a second referendum.”

The SNP’s Ian Blackford offered the Prime Minister some “friendly advice”.

“This deal is dead,” he said. “Stop the charade, and let us get on with putting the decision back to the people once and for all.”

Any hope of May securing cross-party support was dashed when Labour leader Jeremy Corbyn said the offer was “little more than a repackaged version” of her rejected deal.