When will Theresa May resign as prime minister and Conservative leader?

• Theresa May resisted pressure to resign on Wednesday but is widely expected to announce her departure plans as early as Friday.
• The resignation of her Cabinet colleague Andrea Leadsom on Wednesday evening appears finally to have tipped the scales against May,

• One loyal friend of the prime minister told Business Insider the prime minister would likely quit on Friday rather than face the "humiliation" of MPs forcing her out.

• If she fails to do so, Conservative MPs could force a no-confidence vote in June which she would lose.

LONDON - Theresa May is under intense pressure to resign after losing the support of her Cabinet colleagues.

The embattled prime minister, who has proven remarkably resistant to resignation pressure, is unlikely to survive in her post much longer.

The resignation of Andrea Leadsom - the House of Commons leader and May's onetime leadership rival - on Wednesday evening appears finally to have tipped the scales against May, who had already endured a bruising day after a last-ditch attempt to rescue her Brexit plan received a furious backlash.

The question is now how and when, rather than if, the prime minister will leave Downing Street, and whether she will do so of her own volition.

There are two plausible ways in which the prime minister could depart office in the coming days.

She could resign, as she was under intense pressure to do last night. Voting for the European elections is taking place on Thursday, which could explain why the prime minister would have been reluctant to announce any departure plan last night.

Should she resign, Friday would be the first obvious day to do so, with parliament set to enter recess for nearly two weeks afterwards.

Voting in the European elections will also have finished, meaning May's resignation could not be seen to have had an impact on the Conservative vote share, although the party is already polling on disastrously low figures.

Most importantly, Sir Graham Brady, chair of the influential 1922 Committee of backbench MPs, is due to meet with the prime minister on Friday and discuss next steps with his executive committee. He could ultimately force the prime minister's resignation.

The 1922's committee executive held a secret ballot on Wednesday on whether to rewrite party rules to force another leadership contest if May refuses to quit. The results of the vote have been sealed in an envelope, according to ITV's Daniel Hewitt, which will be opened if the prime minister has not resigned or agreed to resign within weeks by Friday.

If May does refuse to leave on Friday, the 1922 plans to change the rules to force another vote of no-confidence in May as Tory leader, which she would lose by a heavy margin.

Will May be out by the weekend?

Current party rules mean the prime minister cannot face a confidence vote in her leadership of the party until December after she survived an attempted coup before Christmas.

However, MPs could change their rules to allow for a vote as early as June.

Even May's allies expect her to announce her departure plan on Friday. One loyal friend of the prime minister told Business Insider that the prime minister would likely quit on Friday rather than face the "humiliation" of MPs forcing her out.

"If she doesn't announce a firm date in the near future she risks the humiliation of the 1922 telling her they are changing the rules and being booted out in a vote of no confidence in a rather undignified way," the MP said.

However, May's resilience has surprised her colleagues before, and it could do so one final time.

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