Italian health minister Pierpaolo Sileri undermined repeated denials from Downing Street that the government wanted the virus to spread in the community to build up a degree of immunity in the population.
Mr Sileri said Guiseppe Conte, the Italian prime minister, had recounted a conversation with Mr Johnson where the UK prime minister had told him he wanted to pursue herd immunity.
The prime minister’s official spokesman said he was not aware of the claims, reported on Channel 4’s Dispatches, but failed to issue a denial when pressed on the issue by journalists.
The spokesman said: “The position of the government is that herd immunity has never been our policy.”
But Mr Sileri told the programme that the prime minister had appeared to advocate for herd immunity in a phone call on 13 March with his Italian counterpart.
“I remember it perfectly because it was the same weekend that I discovered I had Covid,” Mr Sileri said.
“I spoke with Conte to tell [him] that I’d tested positive. And he told me that he’d spoken with Boris Johnson and that they’d also talked about the situation in Italy. I remember he said, ‘He told me that he wants herd immunity’.
“I remember that after hanging up, I said to myself that I hope Boris Johnson goes for a lockdown.”
The government insists that it did not take the controversial strategy to pursue herd immunity, despite comments from the chief scientific adviser Sir Patrick Vallance, who spoke about it openly in interviews.
Experts cast doubt on the idea at the time, saying there was no guarantee people will become permanently immune to the virus once catching it.
A Downing Street readout of the 13 March call with Rome read: “The two leaders discussed the importance of taking a transparent and science-led approach in response to the virus.
“They also agreed on the need for international coordination, including through the G7, and they agreed a call between G7 leaders would be a good opportunity to do that.”
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