UK Prime Minister Boris Johnson has denied saying he would rather “let the bodies pile high in their thousands” than order another lockdown.
The incendiary remark was allegedly made after Mr Johnson reluctantly imposed a second Covid-19 lockdown in England last October.
But the prime minister dismissed the claims as "total, total rubbish" and insisted voters were not interested in the claims.
"The important thing I think people want us to get on and do as a government is to make sure that the lockdowns work," he said.
Downing Street dismissed the claim as "just another lie".
The Daily Mail, citing unnamed sources, reported that the comment was made after Cabinet Office Minister Michael Gove warned Mr Johnson that soldiers would be needed to guard hospitals overwhelmed by Covid patients.
The prime minister is said to have lost his temper after agreeing to a second lockdown, as he insisted there would not be a third.
He allegedly said: "No more … lockdowns – let the bodies pile high in their thousands."
Defence Secretary Ben Wallace said on Monday the report was false.
"It's not true – it's been categorically denied by practically everyone," he told Sky News.
"We're getting into the sort of comedy chapter now of these gossip stories – you know, unnamed sources by unnamed advisers talking about unnamed events. None of this is serious.”
The main opposition Labour party said the allegation was "sickening".
“If this report is true, then these are truly shocking and sickening comments from Boris Johnson,” a spokesman said.
“It is hard to imagine how families who have lost loved ones to Covid will feel reading them. Boris Johnson must make a public statement as soon as possible in his response to this report.”
The reported comment comes amid a public war of words between Downing Street and former chief adviser Dominic Cummings.
In a blog post on Friday, Mr Cummings vowed to give damning evidence to MPs next month about the prime minister’s response to the pandemic after he was accused by Number 10 of a series of damaging leaks, including text message exchanges between Mr Johnson and billionaire businessman James Dyson.
An inquiry by the UK’s top civil servant is currently investigating Mr Cummings over the so-called “chatty rat” leak of plans for a second lockdown.
Appearing before the public administration and constitutional affairs committee of the House of Commons on Monday, Cabinet Secretary Simon Case said that the inquiry was still ongoing but "given the time that has now passed I think it is probable that the team will not successfully identify the source or sources".
He refused to reveal any further information because he said he was "constrained in what I can say because it’s in the context of an ongoing investigation".
Asked about Mr Johnson's reported remark about the Covid death toll, he said it was not something he had looked into but he would discuss the matter with the prime minister.
The civil servant was also pressed on his knowledge of alleged plans by Mr Johnson to use a £58,000 ($80,438) loan from a Tory donor to pay for refurbishments of the Downing Street flat where he and his family live.
However, he said he didn't "have all the facts and details" of the flat refurbishment, and Mr Johnson had ordered him to conduct a review which will "take a matter of weeks".
The tit-for-tat accusations come at a highly sensitive time for Mr Johnson’s administration.
Rows have involved lobbying by former prime minister David Cameron on behalf of financial services company Greensill Capital, the revolving door between business and government and claims that lucrative contracts were awarded to firms during the pandemic without proper scrutiny.
These have deflected attention from the country’s vaccination progress.
The furore also threatens to dominate the final week of campaigning ahead of UK local and mayoral elections on May 6.
Trade Secretary Liz Truss defended Mr Johnson on Sunday, telling broadcasters that Cummings' claims were "tittle-tattle" and that the premier had always "acted in the interests of this country".
She said Mr Johnson had “personally” met the cost of the refurbishment to his apartment – but failed to answer questions on whether Johnson had asked Conservative Party donors to foot the bill.
Accusations from Mr Cummings, who resigned last November, are highly significant because he was at the heart of government.
He had a key strategic role in Britain's exit from the EU, which ultimately helped Mr Johnson to win a landslide general election victory in December 2019.
Mr Cummings's blog post capped a difficult few days for Mr Johnson, which included the resignation of junior defence minister Johnny Mercer, who said the government was “the most distrustful, awful environment I’ve ever worked in”.
Mr Johnson will attempt to ride out the controversy and renew focus on the UK’s vaccination program, which will include 44-year-olds from Monday.