By ITV News Central Production Journalist Victoria Armstrong
A British politics expert has told ITV News Central the Conservative party's nine months of pain made Boris Johnson's resignation inevitable.
Political Professor Tom Caygill, from Nottingham Trent University, says the lack of confidence within the Tory party - following Partygate and allegations against Tamworth MP Chris Pincher - left the Prime Minister with only one option.
Prof Caygill says a lot of work is needed to restore integrity within the party, now that Mr Johnson has resigned.
What happens to the Prime Minister now he has resigned?
The political expert says in "normal circumstances" Mr Johnson would remain leader if the Cabinet approved, similarly to David Cameron and Theresa May's final days in power.
But Prof Caygill warns the attacks from within the party on Mr Johnson's integrity could make that difficult.
Some Conservative MPs are calling for the PM to step down immediately because of his actions and not continue as the caretaker of the position.
Prof Caygill says the chances of that will be slim as "there is no real mechanism for the PM to be removed at this stage."
"There is the possibility the Cabinet could persuade him, but the fact he’s just appointed them, it’s highly unlikely that will happen this afternoon; which suggests they’re happy with him to continue as a caretaker."
Just before the prime minister announced he will act as a caretaker in his resignation speech today (July 7th) he appointed a new Cabinet.
Currently, Mr Johnson will remain Prime Minister until October and the Tory Party Convention.
What happens to the Conservative government now?
On Monday (11 July) the executive elections will be held to determine the timeline for the leadership elections.
Prof Caygill believes the parliamentary process should be complete before the summer recess and says it allows time for party members to decide which candidate they prefer.
His comments come as more than 50 MPs have left Government positions within 48 hours.
"It will be a challenge to fill these vacancies," says Prof Caygill.
Professor Tom Caygill speaks about the next steps for the Conservative Party
He suggested the easiest way to fill these positions would be to convince those who just quit to step in temporarily.
"He's got a challenge there filling those gaps and, of course, given most people who have resigned and been fairly critical of the prime minister it will take a large piece of humble pie for them to come back into government, and for Boris Johnson to accept them."
"It will be a lot harder hiring people from scratch for lower ministerial positions, especially given there seems to be little support from the Conservative party more broadly."
Could a Midlands MP be in the running for the next party leader?
Bromsgrove MP and former Health Secretary Sajid Javid was the first to resign on Tuesday (5 July.
He said he could "no longer, in good conscience, continue serving in this Government," and had lost confidence in Mr Johnson.
Prof Gaygill says his actions could give him credibility for being the next leader.
Tom Caygill talks about Sajid Javid's chances for being the next party leader
Nadhim Zahawi, MP for Stratford-upon-Avon, at first did not resign and supported Mr Johnson. He was appointed as the Chancellor after Rishi Sunak quit.
But less than 48 hours since he became Chancellor, Mr Zahawi wrote a letter to Mr Johnson asking him 'to go now'.
"Zahawi was always going to be risky. He may not be as popular with the party as he was previously," Prof Caygill says.
"I did have him down as a safe pair of hands to take over from Boris Johnson, but I think taking the Chancellorship and then being the person who gave the prime minister a shove out the door might have an impact on him, particularly within the party."
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