Matt Hancock is facing calls to quit as health secretary from fellow Tory MPs after he breached social distancing guidance by kissing a colleague.
The health secretary apologised after pictures emerged of him with Gina Coladangelo, reportedly taken on 6 May.
Conservative MPs Duncan Baker and Sir Christopher Chope have said he should go, while former secretary of state Esther McVey said she would have quit in Mr Hancock’s position.
The PM considers the matter closed.
A Downing Street spokesman said Boris Johnson accepted Mr Hancock’s apology, adding the prime minister had full confidence in the health secretary.
Labour and the Covid-19 Bereaved Families for Justice group have also called for the health secretary to be sacked.
On Friday, The Sun published pictures of Mr Hancock and Ms Coladangelo, who are both married with three children, kissing. It said they had been taken inside the Department of Health on 6 May, leading the health secretary to say he was “very sorry”.
North Norfolk’s MP Mr Baker, who was the first Conservative MP to publicly call for Mr Hancock to quit, told his local newspaper the Eastern Daily Press that the health secretary had “fallen short” on a number of measures.
Ms McVey, Conservative MP for Tatton, told GB News she would have resigned had she been in Mr Hancock’s position and hoped he was “thinking the same thing”.
She added that it would be “viewed more admirably” if he came forward and did not have to have it “pushed upon him”.
Christchurch MP Sir Christopher told BBC Radio 4’s PM programme that Mr Hancock’s position had become “untenable”, saying that his constituents were “seething”.
“For that reason, the sooner he does the honourable thing and announces his resignation, the better – because otherwise it is not going to go away,” he said.
“This is going to run and run, and it will impact adversely upon all of those of us who are involved in public life who are trying to set an example.”
He added that Mr Hancock had been “in charge of making the lives of millions of people a relative misery” but that they had been complying.
“Now he’s shown by his actions, that there’s one law for him and a different law for everybody else.”
Conservative commentator Tim Montgomerie, a former adviser to Mr Johnson, told BBC News Mr Hancock would probably survive in his job as there were concerns in No 10 that his sacking could lead to more scrutiny around other ministers and create a “domino effect”.
Meanwhile, the families of Covid victims warned the breach of social-distancing guidelines could damage government messaging on fighting the virus.
Rivka Gottlieb, from the Covid-19 Bereaved Families for Justice group told BBC Radio 4’s The World Tonight: “If he were to announce another lockdown or further regulations why would anybody listen to someone who doesn’t follow the rules themselves?”
She compared it to the prime minister’s former senior adviser Dominic Cummings’ trip from London to Durham during lockdown last March, when, despite widespread condemnation, Mr Johnson stuck by his aide.
Cabinet colleagues have defended the health secretary with Housing Secretary Robert Jenrick, International Trade Secretary Liz Truss and Transport Secretary Grant Shapps all backing him publicly.