The former cabinet minister became the most senior Conservative to demand his resignation over the ‘partygate’ scandal, intervening during prime minister’s questions.
“You have sat there too long for all the good you have done,” Mr Davis said, reviving a quote first attributed to Oliver Cromwell.
The Commons microphone picked up the Commons Speaker, Lindsay Hoyle, muttering to himself under his breath: “What a day.”
Mr Johnson had put up a fighting performance in the chamber, repeatedly declaring he will not resign ahead of the crucial report by civil servant Sue Gray, who is investigating the controversy.
But Mr Davis then piled on the pressure, as more Tory MPs submit letters demanding a vote of no confidence – with 54 required to trigger that contest.
“I expect my leaders to shoulder the responsibility for the actions they take. Yesterday, he did the opposite of that,” the former Brexit secretary rose to say.
“So, I will remind him of a quotation which may be familiar to his ear: Leopold Amery to Neville Chamberlain [at the outbreak of the Second World War].
“You have sat too long here for any good you have been doing. In the name of God, go.”
Speaking outside the Commons shortly afterwards, Mr Davis pointed to Mr Johnson’s disastrous interview, on Tuesday, in which he said “no-one warned me” the party would break Covid rules.
“It’s not what I expect from a leader. Up until now I had been supporting him...but it’s not leadership,” he told journalists.
“Leadership means shouldering responsibility even when it’s blame. And he didn’t do it. Yesterday’s interview was an attempt to escape responsibility, not to shoulder it – and that is a test of leadership.”
A tweet put out in 2018 by Nadine Dorries, the close Johnson ally and culture secretary, was revived, in which she said: “David Davis is ex-SAS. He’s trained to survive. He’s also trained to take people out.”
But a defiant Mr Johnson later told MPs: “I haven’t sat here quite long enough, indeed nothing like long enough, in my view.”
He also let slip that the Sue Gray report – which is crucial to his chances of surviving the partygate controversy – will not be published until “next week”, prolonging the agony for the Tory party.
The senior civil servant had been expected to finish her work before the end of this week – but her task has grown with further allegations about lockdown-busting events.
As he faced Labour accusations of “absurd and unbelievable” claims about what he knew about the parties, Mr Johnson told MPs to wait until “next week”, for the verdict to be delivered.
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