Boris Johnson has apologised for not wearing a mask on a visit to a hospital last week.

The Prime Minister said it was “barely 30 seconds” that he was not wearing a face-covering during the visit to Hexham General Hospital on November 8.

And he said he put it on as soon as he realised his mistake.

Appearing in front of Parliament’s Liaison Committee on Wednesday, Mr Johnson was questioned by Home Affairs Select Committee chair Yvette Cooper, who said the PM had higher standards to uphold, including on mask-wearing.

Mr Johnson said: “As for not wearing a mask in Hexham Hospital, which you wrap up into my general litany of crime, can I just say that actually, there was barely 30 seconds where I wasn’t wearing a mask.

“I walked out of a room mistakenly not wearing it.

“I then put it on as soon as I realised I made that mistake.

“I apologise for it, but most pictures of my visit to the hospital will show that I was duly masked throughout the remainder of the visit, and I was masked on the way into the visit.”

Following the visit in Northumberland last week, photographs showed Mr Johnson meeting masked nurses at the hospital, talking to them and bumping elbows with them, despite not having his face covered.

Soon after that photo opportunity, the Prime Minister put on a mask, which had been handed to him by an aide.

Northumbria Healthcare NHS Foundation Trust said the Prime Minister “did wear a mask for the majority of the visit”.

But “after the Prime Minister left a welcome meeting, he walked along a mezzanine corridor, for a very short period of time, without a mask”.

“As soon as this was identified he was given a mask and he put it on,” the trust said.

It came after Mr Johnson was pictured at the Cop26 climate change summit sitting alongside 95-year-old environmentalist and broadcaster Sir David Attenborough.

Asked about the use of face masks, Health Secretary Sajid Javid told the NHS Providers annual conference: “Our primary form of defence are the vaccines, that is true the world over, the vaccines remain absolutely critical.

There is a Plan B, there is a contingency plan if we have to go further, and that may include mandatory mask-wearing, it might include other measures

“We’ve got a really high rate of vaccination but yet, that said, there’s still work to be done, there’s still some five million people for example in England that haven’t even received one jab and the booster programme is is critical.

“There is guidance around mask wearing – in some places it is mandatory on public transport… I think people should follow the guidance.”

Asked why the Government in England was not making mask-wearing mandatory, he added: “Each country – whether it’s in different parts of the UK or Europe or elsewhere – they will have to each decide what’s best for them, they will have different sets of measures.

“So for example, we may have different rules of mask-wearing but we also take a much more liberal attitude on testing – many countries in your world charge for their testing.

“So there’s a different suite of interventions that can be made.

“We’ve been clear about which ones we’re taking and why – they’re set out in Plan A.

“But there is a Plan B, there is a contingency plan if we have to go further, and that may include mandatory mask-wearing, it might include other measures.

“We set that out and that is something that is constantly kept under review, if necessary, we will use it.”