An embattled Boris Johnson was hit with two unwelcome surprises in the House of Commons, as ITV News Political Correspondent Carl Dinnen reports
Conservative former Cabinet minister David Davis has urged Boris Johnson to resign over the partygate scandal - the most senior Tory MP to do so.
Mr Davis told the PM he had spent weeks defending him from "angry constituents", including by reminding them of the "successes of Brexit", but said he expects leaders to "shoulder the responsibility for the actions they take".
"You have sat too long here for any good you have been doing. In the name of God, go."
In dramatic fashion, veteran MP David Davis demands Boris Johnson quits
Mr Johnson was laughed at during PMQs as he repeatedly urged MPs to "wait for the inquiry", which is looking into whether he knowingly broke Covid rules by attending a party during lockdown in his Number 10 garden.
Labour leader Sir Keir Starmer said Mr Johnson's excuses for attending the party - that he thought it was a work event and did not know it was in breach of the rules - are "absurd and frankly unbelievable".
It was announced a Sajid Javid will lead a press conference amid the furore over the PM's leadership to update the public on changes to the government's Covid strategy - but he's likely to face questions from journalists about his boss's behaviour during the pandemic.
The PM replied "no" when a Liberal Democrat asked if he would resign over the accusations against him as he again issued an apology for "any misjudgments that were made".
Christian Wakeford, a 'red wall' Tory MP who joined Parliament in 2019 announced he had defected to the Labour Party, just before PMQs began - a crushing blow for the PM.
Has Boris Johnson been pulled back from the brink of a no confidence vote? ITV News' Deputy Politics Editor Anushka Asthana reports on the mood in the Conservative Party
The MP said his decision was "about much more than your leadership and the disgraceful way you have conducted yourself in recent weeks".
He said it was not a last minute decision and took "many months of soul-searching."
"There's been quite a few different issues throughout many months now, whether that's been the free school meals issues, the Patterson issue, Partygate and universal credit."
'It was a jaw dropping moment to see Sir David Davis standing up on the backbenches and saying that it is time for the PM to go,' ITV News Political Editor Robert Peston says
And more Tory MPs are in discussions with the Labour Party about further defections, ITV News understands, with the plot being referred to as "Operation Domino".
As PMQs got underway, a bullish Mr Johnson insisted the Conservatives will "win again in Bury South" after the MP crossed the floor to the Labour Party, but his defence in the face of 'partygate' allegations was much less convincing.
His response to repeated questions about what happened under his watch inside Number 10 during the pandemic - that people should "wait for the inquiry" - was met by a chorus of laughter by Labour MPs.
Bury South MP Mr Wakeford was part of a backbench plot to remove Mr Johnson from office and is understood to have been among more than 20 Tories who submitted letters of no confidence in the prime minister.
How many times did Boris Johnson ask MPs to 'wait for the inquiry'?
An anonymous Cabinet minister told ITV News that Mr Wakeford's defection had established a sense of "unity" among remaining the Tory party, while Conservative MP Jonathan Gullis suggested people have actually withdrawn their letters of no confidence as a result.
ITV News has found that although the atmosphere among the Tories has been febrile over the past few days, rebel MPs have been disappointed that letters of no confidence had not built up on Wednesday.
One rebel MP specified to ITV News that there seems to be more anger towards Mr Wakeford than the prime minister. However, they added that they themselves had not withdrawn their own letter and had not heard of others doing so.
How do Bury South constituents feel about their MP, Christian Wakeford, defecting to Labour?
It is understood that amid Mr Wakeford's and Mr Davis' rebellion, the PM managed to persuade his MPs to withhold letters of no confidence until Sue Gray's investigation into rule-breaking at Downing Street concludes. However, ITV News was met by few answers after asking disgruntled MPs what the investigation could find that would exonerate their leader.
The probe will give a verdict on whether Mr Johnson was telling the truth when he told MPs last Wednesday that he was oblivious to any party that had been planned in the Number 10 garden and assumed he was attending a work event.
There's serious doubt over his claim, given an email was sent by his principal private secretary Martin Reynolds inviting 100 members of staff to "make the most of the lovely weather" by attending "socially distanced drinks" in the Number 10 garden.
Mr Johnson has insisted no one told him about the party but even one of his ministers has accepted millions of people in the UK don't believe him.
SNP Westminster leader Ian Blackford said the prime minister's excuses were "absolutely pathetic" as he called on Mr Johnson to quit.
"The prime minister is taking the public for fools," Mr Blackford said, "nobody believes him. Will the Prime Minister finally take responsibility, resign, go, Prime Minister."
Mr Johnson replied: "No, but I thank him for his question again and let me just remind him that there's an inquiry that is due to conclude. I believe he is wrong in what he asserts, but we'll have to wait and see what the inquiry says."
Deputy PM Dominic Raab and Chancellor Rishi Sunak both said on Tuesday that ministers - the PM included - are expected to resign if they are found to have misled Parliament.
If the investigation, being led by civil servant Sue Gray, finds he did mislead Parliament it is very likely he will either resign of backbenchers will move to have him replaced.
Former foreign secretary Jeremy Hunt has already suggested he would throw his hat into the ring of any forthcoming leadership contest.
Mr Wakeford's defection means there is one less letter of no confidence submitted in the PM, but the threshold to trigger a vote on his leadership remains at 54.
Sir Keir, welcoming the former Tory to his party, said: "The policies of the Conservative government are doing nothing to help the people of Bury South and, indeed, are only making the struggles they face on a daily basis worse.
"I'm determined to build a new Britain which guarantees security, prosperity and respect for all, and I'm delighted that Christian has decided to join us in this endeavour."
Watch PMQs in full: