The head of the civil service described the government as a "terrible, tragic joke" in a series of damning WhatsApp messages shown at the Covid inquiry.
Simon Case - appointed in September 2020 - also suggested Boris Johnson's now-wife, Carrie, was "the real person in charge" as he criticised No 10's handling of the pandemic.
Seemingly at his wits' end over the government's decision-making, he wrote in one message: "Not sure I can cope."
The messages were briefly flashed up on screen during Friday’s hearing of the UK Covid-19 Inquiry in London, as a letter to the inquiry from Mr Johnson’s former adviser Dominic Cummings was shown and discussed. The hearing is part of module two, which focuses on core UK decision-making and political governance.
The letter contained an email dated July 13, 2020, which Mr Cummings said was “on the problems of the No 10/CabOff (Cabinet Office) set up that is relevant to the inquiry”. Mr Cummings said it was copied to the then-PM “but he never engaged seriously”.
The WhatsApp messages appeared on screen above the email and are understood to have been from October 14, 2020. Mr Case, who previously served as permanent secretary in Number 10, wrote: “Am not sure I can cope with today. Might just go home.
"Matt just called, having spoken to PM. According to Matt (so aim off, obvs), PM has asked Matt to work up regional circuit breakers for the North (as per Northern Ireland) today – and to bring recommendations. I am going to scream…”
Lee Cain, who was Mr Johnson’s director of communications until November 2020, replied: “Wtf are we talking about.” Mr Case, in an apparent reference to Mr Johnson’s then-partner and now wife, Carrie Johnson, replied: “Whatever Carrie cares about, I guess.” He also wrote: “I was always told that Dom (Dominic Cummings) was the secret PM. How wrong they are.
"I look forward to telling select cttee tomorrow – ‘oh, f*** no, don’t worry about Dom, the real person in charge is Carrie’.” Further down the messages, Mr Case wrote: “This gov’t doesn’t have the credibility needed to be imposing stuff within only days of deciding not too (sic).
"We look like a terrible, tragic joke. If we were going hard, that decision was needed weeks ago. I cannot cope with this.”
Simon Case's newly-revealed messages raise concerns over the level of influence others may have had over Boris Johnson, explains ITV News Political Correspondent Carl Dinnen
The WhatsApp messages between Simon Case and Lee Cain are eye-popping in more ways than one.Firstly the cabinet secretary is the most senior civil servant in the country, and has been private secretary to David Cameron, Theresa May and Prince William. He is privy to all manner of confidential and secret information.
He is a man from whom you would expect the highest level of discretion, certainly in terms of what he puts in writing.
And then there is what he says. The idea that the prime minister's wife Carrie Johnson was somehow in charge of Downing Street was one that frequently appeared in the newspapers. It was often dismissed as a misogynistic, Lady Macbeth-type caricature.
To see this idea repeated at the time by the cabinet secretary and the Number 10 director of communications is shocking.
It suggests that Boris Johnson really was being pushed in the direction chosen by whoever was closest to him at the time.
This is reinforced by the emoji posted by Lee Cain at the end of the exchange - a shopping trolley.
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