Boris Johnson was doubtful the NHS would be overwhelmed and was reluctant to tighten Covid restrictions as he believed people dying from the virus were "essentially all over 80", new WhatsApp messages released by Dominic Cummings suggest.
The Prime Minister's former chief advisor also told the BBC that the Prime Minister had wanted to let the coronavirus "wash through the country" rather than ravage the economy.
In the his first broadcast interview, Mr Cummings levelled a series of incendiary claims at his former boss - accusing him of putting “his own political interests ahead of people’s lives”.
He told the BBC that Mr Johnson had wanted to see the Queen in person, despite people in Number 10 having been infected with coronavirus in March 2020.
In WhatsApp messages, shared with the broadcaster, that were sent to aides last October, Mr Johnson reportedly wrote: "I must say I have been slightly rocked by some of the data on Covid fatalities. The median age is 82 – 81 for men 85 for women.
"That is above life expectancy. So get Covid and live longer. Hardly anyone under 60 goes into hospital (4 per cent) and of those virtually all survive.
"And I no longer buy all this NHS overwhelmed stuff. Folks, I think we may need to recalibrate.”
"There are max 3 million in this country aged over 80. It shows we don’t go for nation wide lockdown."
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The former aide went on to say that Mr Johnson, who was hospitalised with Covid in April 2020, told meetings in Number 10 that he should never have agreed to the first lockdown.
He also alleged that the PM was too beholden to lockdown-opposing Tories and elements of the media which convinced him the first lockdown was a mistake.
Mr Cummings claimed that Mr Johnson referred to the Telegraph, which previously employed him as a journalist, as "my real boss", and said he repeatedly ignored the advice of his chief scientific and medical advisers.
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"He then basically reverted and said, actually the whole thing was a disaster, we should never have done it, I was right in February, we should basically just ignore it and just let the thing wash through the country and not destroy the economy and move on," Mr Cummings said.
Downing Street said the prime minister had taken the "necessary action to protect lives and livelihoods, guided by the best scientific advice" throughout the pandemic.
A spokesperson added that the government had prevented the NHS "from being overwhelmed through three national lockdowns."
The latest accusations follows a series of claims made by Mr Cummings since he left Number 10.
In a blog post last month, the former aide said Mr Johnson thought then-health secretary Matt Hancock was a "catastrophe" but refused to sack him.
Mr Cummings also released WhatsApp messages last month claiming to show that the PM had called Mr Hancock "f*****g hopeless".