RISHI Sunak has refused to pledge to wear a mask in the House of Commons — as his own government's scientific adviser said vaccines alone won't prevent another Covid spike.

Tory ministers and MPs have come under fire this week for attending the packed Commons without face coverings. That follows the earlier release of Cabinet meeting images showing 30-40 people sitting close together without masks.

Official guidance in England now says that people need only wear masks "when they are with strangers", despite an admission from the government that there's no science to back up the advice that coverings aren't needed when mixing with friends or colleagues. 

When pressed on today's Andrew Marr Show, the Chancellor said he did wear a mask on trains, but stated: "The government guidance is for people to make decisions based on what they think is appropriate based on the circumstances they are in.

"Every workplace is going to be different depending on how many people are there, how long you’re there for, whether you know the people or not. I think people are going to make the decisions that they think are the most responsible ones."

But Professor Adam Finn, who is on the Joint Committee of Vaccination and Immunisation (JCVI), has warned against complacency amidst rising Covid-19 hospital admissions and deaths.

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Appearing on Sky News, he said: "They will go up as the number of cases go up because the virus will reach people who are vulnerable and who may get seriously ill.

"We can't be complacent about this. This is a worsening situation in an NHS which is already under enormous pressure."

And while Sunak and other ministers have said the vaccination programme is the best hope of avoiding a winter crisis, Finn said "many of the hospitalised people we're seeing at the moment are in fact unimmunised people".

Boris Johnson's winter Plan B includes a return to mandatory mask-wearing in England, a measure which hasn't been removed in Scotland.

Labour shadow chancellor Rachel Reeves says that plan should be enacted now. She said: "Sage [Scientific Advisory Group for Emergencies] are saying that some aspects of Plan B, like wearing masks on public transports and in shops, and also working from home more flexibly should be introduced."

Finn told Trevor Phillips on Sky News that vaccines will not be enough to keep the spread of coronavirus under control: "I think that the vaccine programme is doing a lot to make the situation much less severe than it would otherwise be.

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"And the vaccines principally are very effective at stopping people from getting seriously ill.

"They're not so effective unfortunately at stopping infections altogether or stopping the virus from being spread about.

"They do have an effect on that, but they're not by themselves going to be enough at the present time to keep the spread of the virus under control.

"And we do need to see people continuing to make efforts to avoid contact, to avoid transmission, and to do other things as well as get vaccinated if we're going to stop this rise from going up further."

Finn said it is important to "stick to the science" when discussing the prospect of extending the Covid-19 booster programme to people under 50 and offering booster jags at five months rather than six months, stating: "Just giving more people vaccines, including people who maybe don't actually need the vaccines yet, could actually run the risk of making things worse rather than better.

"If you boost people before they actually need the vaccine, it is in some senses a waste of vaccine, but also it means that you are immunising them earlier and they may make a smaller response to the vaccine and that response may wear off earlier.

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"So I think the idea of just getting more doses indiscriminately into people's arms is not really necessarily going to solve the problem.

"I think we do need to focus particularly on the most elderly people and do this in a structured and strategic way in order to have the maximum impact."

And he went on: "I worry in fact that the vaccine programme itself is suffering as a consequence of this suggestion that somehow the problem's gone and we can all go back to normal again, because that will increasingly make people jump to the conclusion that if they've not been vaccinated there's no real need to do it.

"So I do think we need to see a very different kind of message coming from the government now that there is a serious problem, and we all need to continue to contribute to reducing transmission, so that we can get through the winter and the NHS can stay afloat and absolutely we can avoid lockdowns, and the disasters that those bring."

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The UK Government said a further 72 people had died within 28 days of testing positive for Covid-19 as of Sunday, bringing the UK total to 139,533.

Separate figures published by the Office for National Statistics show there have now been 164,000 deaths registered in the UK where Covid-19 was mentioned on the death certificate.