The UK's top civil servant vented that Boris Johnson "cannot lead" amid pandemic-era frustration with the Prime Minister's leadership, according to WhatsApp messages shared with the COVID-19 inquiry.
Simon Case, who remains Cabinet Secretary, told Mr Johnson's then-chief adviser Dominic Cummings that the prime minister was making government "impossible".
The private correspondence, which took place as the Government grappled with the spread of COVID, came during the appearance of former top aide Martin Reynolds at Lady Hallett's probe.
The PM "Cannot Lead"
Mr Case, who has temporarily stepped back from his role due to a "private medical matter", told Mr Cummings that the PM "cannot lead and we cannot support him in leading with this approach".
In the message, read at the hearing, Mr Case said: "I am at the end of my tether. He changes strategic direction every day (Monday we were all about fear of virus returning as per Europe, March etc – today we're in 'let it rip' mode cos (sic) the UK is pathetic, needs a cold shower etc).
"The team captain cannot change the call on the big plays every day. The team can't deliver anything under these circumstances. Decide and set direction – deliver – explain. Gov't isn't actually that hard but this guy is really making it impossible."
It is not the first time that private concerns by Mr Case have made public. Recently disclosed WhatsApp messages saw him describe the Government as looking like a "terrible, tragic joke", while Mr Johnson's wife Carrie was "the real person in charge".
Mr Case, who was made Cabinet Secretary in September 2020 having been permanent secretary in Number 10, had been expected to give evidence to the COVID inquiry in the coming weeks.
Concerns Over "Macho Behaviour"
Mr Johnson's handling of the early days of the pandemic came in for particular scrutiny, as the inquiry launched a major week of hearings that will see Mr Cummings and former Number 10 director of communications Lee Cain appear on Tuesday.
The then-leader, according to a note read from the diary of a former private secretary, asked why the economy was being destroyed "for people who will die anyway soon", in the days before the country went into lockdown.
The diary note from Imran Shafi, which he attributed to Mr Johnson, stated: "We're killing the patient to tackle the tumour. Large ppl (taken to mean large numbers of people) who will die, why are we destroying economy for people who will die anyway soon."
Elsewhere Mr Reynolds, dubbed "Party Marty" due to his role in the partygate scandal, said that Mr Johnson did "blow hot and cold" on various issues while at another he acknowledged concerns about "macho behaviour" and "misogyny" in the top-level management of the crisis. The former principal private secretary also pointed to a "systemic failure" to prepare for the pandemic as he appeared to acknowledge that the realisation of the scale of the disaster had come "late".
Taking questions from Hugo Keith KC, lead counsel to the UK COVID-19 Inquiry, he was asked about a 10-day spell in February 2020 where there "were no communications by email, by Cobra, by boxed notes, with the prime minister during that 10-day period on coronavirus".
Mr Reynolds, who initially said that he could not recall whether there was any "urgent business" during that period, was told by Mr Keith it was half-term.
Government Protocols Were "Grossly Deficient"
The senior civil servant faced repeated questions about whether Downing Street and the Cabinet Office were slow to respond to the impending crisis, as scenes and reports of overwhelmed Italian hospitals began to be broadcast in the UK. "The fact we got into that position is a result of a systemic failure and a failure of the people who are really tracking the situation most closely," he said.
He accepted that Government protocols were "inadequate" and "grossly deficient", while also pointing to the "unusual dynamic" in Downing Street during that period and the influence of Dominic Cummings.
Campaigners from the COVID-19 Bereaved Families for Justice UK group said it had been "hard to keep up with the number of horrific revelations" which emerged from Monday's hearing.