Ministers are split over whether to change government advice on wearing face masks, with Matt Hancock, the health secretary, stressing that the evidence for them was weak despite Scotland’s decision to recommend cloth coverings in some public places. Hancock expressed his scepticism about changing the UK-wide advice in the daily No 10 press conference on Tuesday, emphasising that physical distancing was a much greater priority. However, Whitehall sources said the discussion on the issue was still live among ministers, even though the Scientific Advisory Group for Emergencies (Sage) presented its verdict on the issue to the cabinet almost a week ago, which is understood to have advised there was little evidence masks reduce the spread of infection in the community. One government source said there was still clear concern among some ministers about changing the UK advice at this stage, when people with symptoms are being advised to stay at home anyway. “There is a worry in government is that we don’t want to do anything to lessen the impact of masks for healthcare workers. The risk is that you end up with people in the NHS without masks. We are being very cautious about it. There are people in government who obviously are more and less enthusiastic about the idea,” the source said. However, some ministers are persuaded of the idea that people might feel more confident about going back to work if they are told to wear cloth coverings on public transport and in enclosed work spaces, which could help reopen the economy. The British Medical Association has also called on ministers to make wearing masks in public compulsory. On Tuesday Nicola Sturgeon announced new non-mandatory guidance recommending that the Scottish public should wear face masks in enclosed spaces where social distancing is difficult to achieve, for example while shopping or using public transport. The Scottish first minister said she had taken advice from Sage, as well as her own chief medical officer, before making the decision to advise the use of masks “in limited circumstances”. Sturgeon said one of the reasons she had issued the guidance now was because people were increasingly wearing masks when they left the house and she did not want this to make individuals feel “invincible’ or distract from adherence to existing physical distancing and stay-at-home guidance. She told reporters at her daily media briefing “all governments across the UK are considering this and it’s not for me to speak to them”, insisting there was no “divide or split” between them on the matter. Asked about the issue later at the No 10 press briefing, Hancock said: “UK government advice hasn’t changed, not least because the most important thing people can do is the social distancing, as opposed to the weak science on face masks. “There is very clear science on social distancing and the importance of it. That is the absolute priority in terms of the message to the public. The social distancing and staying at home is the thing that’s helping to save lives. That is the number one thing.” Professor Dame Angela McLean, the UK deputy chief scientific adviser, confirmed that Sage recommended that 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”. McLean said: “Under our current circumstances, anybody who has symptoms really must stay at home ... 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,” she said. “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.”