Boris Johnson has claimed Britain’s Covid-19 vaccine programme would still be at the “starting blocks” under Sir Keir Starmer, as the pair clashed in the House of Commons

The Prime Minister said the Labour leader had repeatedly called for the UK to stay in the European Medicines Agency, and suggested such a move would have hampered the UK’s response to the pandemic.

But Labour leader Sir Keir described the remarks as “complete nonsense” and suggested the “truth escapes” the Prime Minister.

Mr Johnson pulled faces and puffed his cheeks in response to Sir Keir’s answer.

Comments from Sir Keir contained in Hansard, the official record of Parliament, in January 2017 show him questioning why the UK would want to leave the body and that it should be something retained as part of the Brexit process.

Conservative former minister Mark Francois later raised a point of order in a bid to correct the record and highlight Sir Keir’s previous remarks.

A spokeswoman for Sir Keir said the Labour leader “misheard” the Prime Minister and assumed he was repeating “false accusations” about Labour wanting to join the EU’s vaccine programme rather than referring to the European Medicines Agency.

Speaking at Prime Minister’s Questions, Mr Johnson said: “If we had listened to (Sir Keir), we would still be at the starting blocks because he wanted to stay in the European Medicines Agency and said so four times from that despatch box.”

Sir Keir responded: “Complete nonsense. Don’t let the truth get in the way of a pre-prepared gag.

“The Prime Minister knows I’ve never said that, from this despatch box or anywhere else, the truth escapes him.”

The spokeswoman for Sir Keir later said in a statement: “Keir accepts that, on this occasion, the Prime Minister was referring to old comments about the European Medicines Agency and Keir admits he was wrong and made a mistake in his response.

“It’s not Labour policy to join either the European Medicines Agency or the EU vaccine programme.”

Opening Prime Minister’s Questions, Sir Keir earlier questioned why further measures had not been taken at the country’s borders.

He said: “Today we’re likely to hit 10 million vaccinations, which is remarkable. The biggest risk to the vaccine programme at the moment is the arrival of new variants such as the South African variant.

“On that issue, the Government’s own scientists Sage said two weeks ago, and I quote, ‘only a complete pre-emptive closure of borders or the mandatory quarantine of all visitors upon arrival can get close to fully preventing new cases or new variants’. So, pretty clear.

“So why did the Prime Minister choose not to do the one thing that Sage said could prevent new variants coming to the UK?”

Mr Johnson replied: “Actually, Sage did not recommend a complete ban and they say travel bans should not be relied upon to stop the importation of new variants.

“But we do have one of the toughest regimes in the world.”

He added: “They will have an isolation assurance agency checking up on them and it is illegal now to go on holiday in this country, it is illegal to travel from South Africa or all the countries on the current red list and we will be going forward with a plan to ensure people coming into this country from those red list countries immediately have to go into Government-mandated quarantine hospitality.”

Sir Keir countered: “He doesn’t seem to dispute that, he says it simply wasn’t a recommendation.

“I would ask the Prime Minister to publish the full Sage minutes so that we can see what was said in full or if there’s some other advice, perhaps publish that.”

Mr Johnson replied: “It is not practical completely to close off this country as he seems to be suggesting. What is practical to do is have one of the toughest regimes in the world and to get on with vaccinating the people of this country.”

Sir Keir went on to ask why the Prime Minister thinks that new variants will “only arrive in the UK from direct flights”.

Mr Johnson responded: “(Sir Keir) can’t have it both ways. He simultaneously says that he wants the borders to be kept open for freight reasons or to allow businesses to carry on, I think that was what he was saying, whilst calling for tougher quarantine measures, which is exactly what this Government imposed as soon as we became aware of the new variant.”