Both Professor Sir Patrick Vallance and Professor Chris Whitty have said they will continue to wear a mask in crowded indoor spaces, after the government announced that face coverings will no longer be compulsory from later this month.
"We will move away from legal restrictions and allow people to make their own informed decisions about how to manage the virus," prime minister Boris Johnson said in a Downing Street press conference on Monday.
The change in guidance – set to come into force from 19 July, pending a final decision next Monday – will mean people can down masks after 18 months of enforced face covering, though businesses and transit operators may still require them.
Prof Vallance, England’s chief scientific adviser, and Prof Whitty, the chief medical officer, both outlined their intention to keep wearing masks where appropriate.
Prof Whitty highlighted three scenarios where he would continue to wear a mask: in “any situation which is indoors and crowded”; when "required to by any competent authority”; and out of “common courtesy” if “someone else was uncomfortable if I didn't wear a mask”.
The PM similarly committed to wearing a face covering in crowded places full of strangers, but suggested he would not do so on an empty train carriage late at night.
"I will obviously wear a mask in crowded places where you are meeting people that you don't know, as Chris [Whitty] was saying, to protect others and as a matter of simple courtesy,” he told the press conference.
"There's a difference between that … and circumstances where you might find yourselves sitting alone for hours late at night on a train with no one else in the compartment and there I think people should be entitled to exercise some discretion."
Sir Patrick Vallance meanwhile warned that "deaths are increasing" and "we would expect that to continue" as Covid cases rise, as he said people must "behave accordingly in terms of trying to limit transmission".
The chief scientific adviser said that infections are "going up" and that "the link between cases and hospitalisations and cases and deaths is weakened but not completely broken, and we would expect to see some further increase".
He told the Downing Street press conference that "we are in the face of an increasing epidemic at the moment and therefore we need to behave accordingly in terms of trying to limit transmission".
Documents released by the government’s Scientific Advisory Group for Emergencies (Sage) also emphasised the need for keeping infections low in the community.
“There is significant risk in allowing prevalence to rise, even if hospitalisation and deaths are kept low by vaccination,” Sage scientists said. “If it were necessary to reduce prevalence to low levels again … then restrictive measures would be required for much longer.”
The PM admitted that there could be 50,000 reported infections a day by 19 July, when other restrictions such as social distancing and the one-metre rule are to be scrapped.
Britain is also still weighing up whether the benefits of vaccinating children against Covid-19 outweigh the risks given their low rate of severe outcomes from the disease, Prof Whitty said.
He said officials were still getting "all the data before they give final advice".
"For any vaccine, what you want to be confident of is that the benefits of the vaccine outweigh any risks of the vaccine for the children involved," he added.