UK's Boris Johnson agrees to quit, will be 'caretaker PM' till October

British prime minister Boris Johnson on Thursday resigned as leader of the ruling Conservative Party and said he would step down as PM once his successor is chosen. Johnson's resignation came after an exodus of ministers over the past three days, amid outrage triggered by the promotion of Chris Pincher, who faces sexual assault allegations. An internal election to choose a new party leader, and de facto prime minister, will likely be completed by October, the BBC said.

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Reports that Johnson was ready to quit came minutes after yet another minister walked out of the prime minister's cabinet. News agency AFP said education minister Michelle Donelan told Johnson 'I see no way you can continue...', and finance minister Nadhim Zahawi urged the PM follow his 'heart' and 'go now' .

"I see no way you can continue in (your) post but, without a formal mechanism to remove you, it seems the only way... is for those of us who remain in (the) Cabinet to force your hand," Donelan said according to news agency AFP.

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Zahawi - also appointed just 48 hours earlier and seen by some as a potential successor - tweeted calling on Johnson to 'do the right thing and go now'. "Prime minister, you know in your heart what the right thing to do is, and go now," Zahawi - who was also appointed two days ago - said.

Earlier home minister Priti Patel conveyed to Johnson the Conservatives; 'general view'; "... Patel told Johnson that the general view of the Conservative party was that he had to go," American cable news channel CNN reported.

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Over 50 junior and senior members of Boris Johnson's cabinet, as well as high-ranking officials have walked out since ex finance minister Rishi Sunak and the former health minister Sajid Javid quit Tuesday.

READ | ‘Cannot continue like this’: What Rishi Sunak said as he quit

With his back to the wall, Johnson on Wednesday sacked Michael Gove in a shock move; a Downing Street source told the BBC the PM called Gove a 'snake'.

Anger and discontent against Johnson - which remained bottled up through a number of scandals, including 'partygate' - erupted after the way he dealt with sexual misconduct allegations against ex deputy chief whip Chris Pincher.

It has been suggested Johnson knew about the allegations but still chose to promote Pincher to a senior position; Chris Pincher resigned last week.

Nevertheless, till late Wednesday night Johnson dug in and vowing to 'fight on'. "The prime minister is in buoyant mood and will fight on," James Duddridge, his private parliamentary secretary, told Sky News.

READ | UK PM Boris Johnson fires ally and digs in despite calls to quit

Johnson only narrowly survived a no-confidence vote among Conservative MPs last month; 211 voted for the prime minister but a staggering 148 stood against him. This, ordinarily, means he cannot be challenged again for another year.

That rule, however, is reportedly being changed by the influential '1922 Committee', and another vote would likely have meant defeat for Johnson.

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With input from AP, AFP, Reuters