Boris Johnson has insisted his Government at “every stage tried to minimise loss of life” as he failed to deny claiming Covid was “only killing 80-year-olds”.

Sir Keir Starmer used Prime Minister’s Questions to grill Mr Johnson over allegations levelled against the Government, predominantly by his former senior adviser Dominic Cummings.

At one stage the Labour leader asked Mr Johnson to refute an allegation that he delayed introducing a second lockdown last autumn because “Covid was only killing 80-year-olds”, with Mr Johnson replying that the independent public inquiry will examine the matter, before defending his decisions.

SNP Westminster leader Ian Blackford also asked about claims that the Government considered “chickenpox parties” and “injecting the Prime Minister with Covid live on TV”.

Mr Johnson replied: “I don’t recognise the events he describes.”

Opening Prime Minister’s Questions, Sir Keir focused immediately on evidence provided by Mr Cummings to MPs at a parliamentary hearing.

Sir Keir said: “This morning the Prime Minister’s former closest adviser said: ‘When the public needed us most, the Government failed’ – does the Prime Minister agree with that?”

Mr Johnson replied: “The handling of this pandemic has been one of the most difficult things this country has had to do for a very long time and none of the decisions have been easy.

“To go into a lockdown is a traumatic thing for a country, to deal with a pandemic on this scale has been appallingly difficult, and we have at every stage tried to minimise loss of life, to save lives, to protect the NHS, and we have followed the best scientific advice that we can.”

Sir Keir went on to ask if the Prime Minister accepted his “inaction led to needless deaths”, with Mr Johnson replying: “No, Mr Speaker, and all those matters will be reviewed in the course of the public inquiry that I have announced.

“I notice he is fixated, as ever, on the rear-view mirror.”

Mr Johnson went on to deny the Government had been “complacent” over threat posed by Covid-19.

Sir Keir went on: “Another central allegation briefed overnight is that the Prime Minister delayed the circuit-break over the autumn half term because ‘Covid was only killing 80-year-olds’.

“Can I remind the Prime Minister that over 83,000 people over 80 lost their lives to this virus and that his decision to delay for 40 days from the Sage guidance on September 21 until October 31 will be seen as one of the single biggest failings of the last year?

“Does the Prime Minister accept that he used the words ‘Covid was only killing 80-year-olds’, or words to (that) effect?”

Mr Johnson replied: “Of course this will be a matter for the inquiry to go into … I am absolutely confident that we took the decisions in the best interests of the British people.

“When it comes hindsight, just to remind (him) … that he voted to stay in the European European Medicines Agency which would have made it impossible for us to do the vaccine rollout at the pace that we have.”

Sir Keir countered: “I note that the Prime Minister’s careful not to refute these allegations.

“What we’re seeing today is the latest chapter of a story of confusion, chaos and deadly misjudgments from this Government. From a Prime Minister governing by press release, not a plan.”

He added: “In the light of the drip of these very serious allegations and the failure of the Prime Minister to provide even basic answers, and continuing mistakes affecting millions of people, does the Prime Minister now recognise he must bring forward the timing of the public inquiry into Covid and that it should start this summer and as soon as possible?”

Mr Johnson replied: “No, as I’ve said before I’m not going to concentrate valuable official time on that now whilst we’re still battling a pandemic, and I thought actually that was what the House had agreed on.”

He pointed to the vaccination rollout, adding: “He continues to play these pointless political games whilst we get on with delivering on the people’s priorities … They vacillate, we vaccinate; they deliberate, we deliver.”