Cummings has told a UK government select committee that the UK government failed the public over its response to the pandemic.
Boris Johnson's former chief adviser, Dominic Cummings, said that the UK prime minister considered COVID-19 to be a "scare story" and that the government's strategy had failed the British public.
Johnson said key people in government and in No 10 were skiing in the middle of February 2020 as the COVID-19 pandemic began to take hold.
Speaking to a parliamentary committee on Wednesday, Cummings said: "The government and No 10 was not operating on a war footing in February. Lots of people were literally skiing," he said.
Cummings is giving evidence to the committee about the British government's response to COVID-19.
He told the committee that the COVID-19 response was a case of "lions led by donkeys" and that senior officials including Johnson, Health Secretary Matt Hancock, and himself had failed the public.
Over the past few weeks, he has made explosive claims about the government and Johnson's own response to the pandemic, including claims that Johnson said that he was willing to let "bodies pile up in the streets" rather than take the UK into a third lockdown.
'A scare story'
Asked on a number of occasions about that quote, which Johnson has denied, Cummings did not elaborate on it.
But Cummings did say that Johnson saw COVID-19 as "a scare story" in February 2020 and compared it to swine flu.
He also said that the controversial idea of herd immunity - letting people get sick with COVID-19 to enable natural immunity build-up in society - was very much part of the government's strategy in March 2020 because Johnson believed the British public would never accept a lockdown.
When Hancock said on March 15, 2020: "We have a plan. Herd Immunity is not part of it" he was lying, Cummings said.
"I am baffled as to why No. 10 is trying to deny it," Cummings told the committee.
'We're completely f**ked'
He said that he had repeatedly called for Hancock to be fired for lying to the British public and to officials in meetings, as well as for procurement during the early weeks of the COVID-19 pandemic.
Cummings also said that officials in No. 10 realised as late as mid-March that there was no strategy for dealing with COVID-19.
"There is no plan. We’re in big trouble. We're going to kill thousands of people. I think we are absolutely f**ked," a senior official said.
He described the strategy in Whitehall as "an out of control movie".
Cummings is referred to in the UK media as 'Nuclear Dom' due to his outspoken and controversial pronouncements. He outlined much of what he planned to say in a 42-tweet tirade posted between May 17 and May 22.
Cummings was the former director of the Vote Leave campaign which led the campaign to take the UK out of the European Union. When Johnson became prime minister, he joined him in Number 10 as an advisor but was sacked by Johnson in November 2020.
His own actions during the pandemic have seen him make headlines, including when it emerged that he had broken the government's lockdown rules to go on a drive to a castle in northeast England. In a widely ridiculed press conference he later said he did so to test his eyesight.
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