BORIS Johnson fired a four-letter rant at Matt Hancock for misleading him over the care home testing fiasco.
The PM flew into a rage after returning from his own Covid battle to find elderly residents had been released from hospital still infected.
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He yelled at the Health Secretary: “What a f***ing mess.”
Cabinet members were so shocked by the failure some are said to have urged him to fire Mr Hancock.
The angry exchange was revealed after former No10 adviser Dominic Cummings claimed the disastrous handling of the pandemic had cost tens of thousands of lives.
He claimed the Health Secretary should have been fired for 15 to 20 different things, including lying.
A source said last night three ministers called for Mr Hancock to go. But the PM is said to have replied: “It would be intolerable to sack my health secretary in the middle of a pandemic.”
Mr Johnson learned of the testing blunder after his stay in an intensive care unit with the virus.
He discovered Mr Hancock had sent thousands back to care homes even though they could spread it.
Mr Cummings claims Mr Hancock misled the Cabinet by saying patients would be tested before leaving hospital.
It was made worse as homes were struggling with PPE shortages.
The insider said: “Boris returned from convalescence at Chequers when he heard the news. He was incensed.
“Matt had told him point blank tests would be carried out. He couldn’t understand why they hadn’t been. For a moment he lost it with Matt, shouting ‘What a f***ing mess’.
“At least three ministers told Boris Matt should be sacked.”
Mr Hancock denies lying about care home policy but accepts testing took longer than expected.
Bizarrely, the PM is unlikely to fire the Health Secretary now for fear of being seen to bow to pressure from Mr Cummings.
Tory MPs believe he is using him as a human shield to take criticism of his handling of the pandemic.
An insider said: “He’s become a lightning rod for the PM.”
A Health Secretary ally said last night: “We completely reject claims made by Dom around honesty including in relation to testing.”
And a No10 source said: “The PM thinks Matt Hancock worked incredibly hard throughout.”