In one extraordinary intervention last week, Danny Kruger – Mr Johnson’s former political secretary, who is now MP for Devizes and a ministerial aide – warned that many people “have decided they cannot vote for us again while Boris Johnson is leader”.

He added:  “To win them back, and to fulfil our duty to everyone in the country including those who didn’t vote for us, we need good leadership,” highlighting the need for a chief of staff “who will grip the operation in No 10”.

Mr Ellwood agreed, saying: “You need a new chief of staff, there’s no doubt about it.” The former defence minister said he even feared that Vladimir Putin may be emboldened by Mr Johnson’s political misfortunes, in the Russian president’s designs on Ukraine. 

“A simple glance at the domestic headlines would tell Putin that Britain is not a voice to worry about,” he said.

On Saturday Peter Bone, the MP for Wellingborough and a supporter of Mr Johnson, told The Times: “If there were people in Downing Street prior to the Duke of Edinburgh’s funeral partying, well they’re prats and need to be sacked.”

Julian Knight, chairman of the Commons culture select committee, said he was “very open minded” about the possibility of Mr Johnson being removed from office, following “extreme stupidity” by people in No 10.

Writing in The Telegraph, Chris Loder – who was elected as MP for West Dorset in 2019 – said: “This is now becoming a matter where the integrity of all of Westminster is being questioned, as well as that of the Downing Street party animals.

“I am clear that the apology made by the Prime Minister in the House of Commons last week was not enough.” 

Jeremy Hunt, the former foreign secretary, has said emails from constituents had been “red hot with anger” over the issue, while Gary Sandbrook, an executive secretary of the 1922 Committee and one of the 2019 Red Wall MPs, said: “I would expect anyone who is found to have broken the law to seriously consider their position in government, and that includes the Prime Minister.”

Tories await outcome of Sue Gray’s inquiry

The refrain by many Tories that they will wait for Ms Gray’s findings before coming to their own conclusions is in some cases a smokescreen for those who have decided that it is a case of when, not if, the Prime Minister has to step down.

Some still hold out hope that Mr Johnson can carry out the changes necessary to “reset” the Government and reverse a decline in the polls. They point to the Prime Minister’s success overseeing the mass roll-out of Covid-19 vaccines, as well as his policies to “level up” the country.

Elliott Weaver, the chairman of the Bethnal Green and Bow Conservative Association, said: “If the Prime Minister wants to stay in post, he needs radically to shift gear so that we are showing the country the benefits of governing with actual progressive Conservative policies and values.

“The past two years has shown that Boris … doesn’t have a good set of advisors and experts around [him] to make the best decisions. Boris needs to act on this within days … otherwise the party will need a new leader to grapple with these new challenges.”

A reset “might work if they get a few lucky breaks in Sue Gray’s report”, one MP said of the current No 10 operation.

“They will need to make some big commitments on freedoms from Covid restrictions, and the Levelling Up white paper needs to be bold.” But the Prime Minister will “need to do something with people” – specifically carrying out a reshuffle of his top team.

Senior officials believe that Ms Gray’s report could, at least, lead to Martin Reynolds, Mr Johnson’s private secretary, being moved out of No 10. It follows anger over the leaked email in which he invited Downing Street staff to “socially distanced drinks in the No 10 garden” to “make the most of the lovely weather” on May 20 2020, despite stringent Covid-19 measures in place at the time.