The UK government has effectively dismissed the Scottish government's new advice that people should wear face coverings in shops and on public transport, saying evidence for the measure is "weak".

In the latest departure from UK-wide coronavirus guidance, Scotland's First Minister Nicola Sturgeon announced that cloth coverings should be used when social distancing was hard to maintain.

But, asked whether the recommendation was likely to be adopted across the UK Health Secretary Matt Hancock said the government's position had not changed and that there was "weak science" supporting the advice.

:: Listen to the Daily podcast on Apple Podcasts, Google Podcasts, Spotify, Spreaker

Speaking at the daily coronavirus briefing, Professor Angela McLean said the government's scientific advisory committee, Sage, found there was "weak evidence of a small effect in which a face mask can prevent a source of infection going from somebody who is infected to the people around them".


She said: "Under our current circumstances, anybody who has symptoms really must stay at home - that's the thing that people have done so brilliantly - but we are also concerned that some people are infected who don't have symptoms, or maybe don't have symptoms yet, and that is the reason that Sage has put so much effort into looking at this question.

"But the answer is clear that the evidence is weak and the effect is small, and we have passed that on to our colleagues in government with which to make a decision."

The new recommendations for everyone in Scotland above the age of two to wear face coverings made of cloth, including scarves, applies on public transport and in shops.

"We are recommending that you do wear a cloth face covering if you are in an enclosed space with others where social distancing is difficult, for example public transport or in a shop," Nicola Sturgeon said during her daily COVID-19 briefing.

Ms Sturgeon's use of the more general term of coverings distinguishes them from the use of medical-grade masks, amid fears an increased public uptake could cause a shortage for NHS workers.

Scotland has stopped short of making their use mandatory, conceding evidence over their use was "still limited".

But the first minister said there were benefits in wearing coverings to reduce transmission from individuals who are not yet exhibiting symptoms.

Minute silence for key workers who have died

Leaders across the UK have all said they want to maintain a unified response to the pandemic.

But Ms Sturgeon has warned she "will not hesitate" in taking Scotland in a different direction, while the Welsh government announced an extension to the lockdown ahead of other nations last week.

The new advice was broadly welcomed by experts, although some said officials should reveal any new evidence that had prompted the decision.

Trish Greenhalgh, professor of primary care health sciences at Oxford University Nuffield Department, said the Scottish government's decision on face masks was "a common-sense way of reducing the transmission".

She said: "They are as evidence-based as school closures, handwashing and lockdown, in that none of these measures is supported by definitive randomised controlled trials but all are supported by other kinds of science."

Ian Jones, professor of virology at the University of Reading, said the decision was in line with other European countries and was "simply, a no-brainer".

"The arguments against mask use always centre on if they are worn appropriately, if they lead to a false sense of security or if their use will limit supplies," he said.

"But the real scientific question is 'can they reduce transmission' and the answer to that is yes."

But Keith Neal, emeritus professor of the epidemiology of infectious diseases at the University of Nottingham, suggested the decision was political and not supported by evidence.

"It is impossible to know why this has been suggested now given there has been no change in the evidence," he said.

"The decision seems political given it is against the Scottish and other UK scientific advice that has been given. There is no indication to make this UK wide due to the lack of evidence and strong possibility that they will not work."