Cabinet Minister Nadine Dorries has admitted Tory preparations for the pandemic were "inadequate" as she tried to attack a top critic of Boris Johnson.
In a ferocious Twitter rant, Ms Dorries tore into her fellow Conservative Jeremy Hunt after he said he would vote to oust Mr Johnson.
Tory tensions boiled over after 1922 Committee chief Sir Graham Brady confirmed that a vote of no confidence would be held tonight, which could topple Mr Johnson.
Ms Dorries, a Johnson fanatic, accused the former Health Secretary of recommending that the UK follow China's example by placing people in isolation hotels.
"Your handling of the pandemic would have been a disaster," she blasted in an extraordinary blue-on-blue attack.
She also said he'd claimed the Government would collapse after Brexit, adding: "You’ve been wrong about almost everything, you are wrong again now."
But her attack on Mr Hunt spectacularly backfired when she admitted that the Tory Government's pandemic preparedness during his tenure "was found wanting and inadequate".
Shadow Health Secretary Wes Streeting seized on her comments as a "damning indictment" of botched planning ahead of the Covid pandemic.
He tweeted: "Conservative Cabinet minister admits that their pandemic preparation was ‘found wanting and inadequate’.
"This is a revealing admission and damning indictment of the Conservatives’ pandemic preparedness. They’re not fit to govern."
And Labour's deputy leader Angela Rayner said: "They failed to keep us safe. You just can’t trust them."
Ms Dorries told Sky News that it was "utterly bizarre" that some MPs were trying to remove Mr Johnson after he won a landslide in 2019 election.
She said 14 million people had elected the PM - which is technically inaccurate as Prime Ministers are not directly elected by the public, who vote for their local MP.
"I find it utterly bizarre that a small number of MPs think that they can overrule that vote of 14 million people," she said.
"It's quite something that they think they can do that and so let's get this vote done, let's move on tomorrow.
"The Prime Minister is going to win comfortably tonight and we can move on."
Mr Johnson is fighting for his political life as he faces a crunch vote on his leadership in the Commons tonight.
The PM must retain the support of half of the Tory party in a secret ballot to remain in Downing Street.
At least 15% of Conservatives - some 54 MPs - have written letters to the 1922 backbench committee expressing no confidence in his leadership.
But 180 MPs must vote against him to remove him from No10.
Cabinet ministers were dispatched to broadcast studios to express their backing for the PM, while loyal Tories have been tweeting their support.
Brexit Opportunities Jacob Rees-Mogg said many Tory MPs "owe their seats directly to Boris Johnson" in a warning to restive backbenchers.
But the PM's anti-corruption tsar John Penrose quit his post and accused the PM of breaking the ministerial code over Partygate.
And ex-minister Jesse Norman published a blistering letter where he told Mr Johnson that his response to Sue Gray's report had been "grotesque".
Downing Street said Mr Johnson will not be distracted from the business of government by the confidence vote - and said he had been speaking to the Ukrainian President Volodymyr Zelensky this morning.
The Prime Minister's official spokesman said: "The Prime Minister is firmly of the view that he will not be distracted from the key issues facing the UK and the world.
"That is illustrated by the call he had with Zelensky this morning.
"Equally there are key domestic challenges - not least the Covid backlog, the cost-of-living pressures - I think he will be taking more action on in due course."
