Mr Davis, a Tory grandee and former minister, stood up in the House of Commons on Wednesday and told the prime minister: "In the name of God, go."

He is the most senior Conservative to call for Mr Johnson to resign, saying the PM had failed to take responsibility for his actions over lockdown parties in Downing Street.

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Health Secretary Mr Javid told Kay Burley on Sky News: "I've known David Davis for many years, got huge respect for him, we don't always agree on everything and that is one thing I don't agree with him on.

"It is damaging, of course it is. If you said to me would I rather he didn't get him and say something like that then, of course, I wouldn't want to see that but that's the decision he made.

"The prime minister has come to the House of Commons last week, he has set out and apologised, set out what has happened but most importantly I think he has asked for this investigation to be done, for the time and space to be given for it to be completed and the facts to be established.

"And once they are, the PM will come very quickly back to parliament and submit himself so David Davis, or anyone else, can ask them whatever question they want."

Just moments before Prime Minister's Questions on Wednesday, where Mr Davis called for the PM's resignation, Bury South MP Christian Wakeford defected from the Conservatives to Labour.

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Mr Javid said he "was sad to see Christian go" and admitted it is "never good for any political party to see one of your own leave and defect".

He added: "I feel sorry for the people of Bury South, they voted Tory.

"I think a by-election would be welcome, I think Christian would be happy with a by-election.

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"Given the people of Bury South rightly voted Conservative in 2019, they wanted to get Brexit done, they wanted to see a strong economy and now they've got an MP that has changed his affiliation without their permission, why not give them a say?"

The Labour Party has said it does not want a by-election, with shadow chancellor Rachel Reeves telling Sky News we should wait until the next general election.

Mr Wakeford's defection came soon after about 12 Conservative MPs, also from the 2019 intake, handed in letters of no confidence in the prime minister.

The PM's premiership looked very rocky on Wednesday morning but many Conservative MPs used PMQs to stand up and express their support for Mr Johnson.

However, this has not halted talk of him being ousted and a leadership race taking place soon.

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Mr Javid is high on the list of potentials to replace Mr Johnson and would not rule out running.

"There's a good line-up of talent I would say in the party there and so there is no leadership election, we have got a PM he is getting on with the job and that is what matters," he told Sky News.

"There is no leadership election."