Boris Johnson has said Eat Out to Help Out was not a seen as a “gamble” at the time and that he was “perplexed” at the suggestion top scientists were unaware of the scheme.

Leading Government scientists, as well as former health secretary Matt Hancock, have claimed they were not told in advance about Rishi Sunak’s scheme – when he was chancellor – to revive the hospitality industry in the summer of 2020.

The plan formed part of Mr Sunak’s summer economic update on July 8 2020, and provided 50% off the cost of food and/or non-alcoholic drinks.

I don’t think that I thought that scheme in itself was a particular gamble at the time and it certainly wasn’t presented to me as such

It has been heavily scrutinised by the inquiry, with questions about whether scientists were consulted about the plan and whether it contributed to the spread of infection.

Mr Johnson told Lady Hallett’s probe: “I don’t think that I thought that scheme in itself was a particular gamble at the time and it certainly wasn’t presented to me as such.”

He said that he cannot see anything that “conclusively shows” the scheme had an impact on the reproductive rate of the virus.

“At the time that the Eat Out to Help Out policy was being aired with me for the first time, it was not presented to me as an acceleration, simply something to make sense of the freedoms that we were already giving.

“I must emphasise, it was not at the time presented to me as something that would add to the budget of risk,” he said.

Mr Johnson also expressed surprise at the suggestion senior scientists were unaware of the scheme and said it was “funny” to hear England’s chief medical officer Sir Chris Whitty later calling it the “eat out to help the virus”.

Sir Chris has told the inquiry that he and Sir Patrick Vallance, the Government’s former chief scientific adviser, were never told about the plan.

The former deputy chief medical officer Professor Sir Jonathan Van-Tam also said he first heard about Eat Out to Help Out on television, while chief scientific officer Dame Angela McLean has claimed she was also not consulted.

In evidence submitted to the inquiry, Mr Sunak said he “(did) not recall any concerns about the scheme”.

Mr Johnson said he “thought that Chris and Patrick must have known” and repeatedly said he did not understand how the plan could have been “smuggled past” the scientists.

“I am fairly confident it was discussed several times at meetings at which I believe they must have been present.

“I remember being surprised, later, I think it was in September, when Chris says ‘this is eat out to help the virus’.

“And I thought, ‘well, that’s funny’, because I didn’t remember any previous controversy about it.”

The former prime minister on Wednesday admitted he should have “twigged much sooner” about the threat posed by Covid-19 in the early days of the pandemic, but he also sought to defend his administration from claims of toxicity and dysfunction.

Relatives of Covid-19 victims gathered again outside the inquiry building at Dorland House in west London. Mr Johnson on Wednesday apologised for “the pain and the loss and the suffering” of victims.

In a full day of evidence that focused on the early stages of the pandemic and the decision to introduce the first lockdown, Mr Johnson also defended the under-fire former health secretary Matt Hancock.

His final day of evidence is expected to focus on the later stages of the pandemic and the decision to apply a second lockdown.

The Prime Minister will give evidence to the inquiry on Monday.