Family gatherings at Christmas can be made “relatively safe” if coronavirus cases are brought under control with stringent restrictions, a Government scientific adviser has said.

Professor John Edmunds, a member of the Scientific Advisory Group for Emergencies (Sage), made the comments as the Government considers imposing a national lockdown next week.

Boris Johnson is to announce new measures which could see everywhere except essential shops and education settings closed for a month.

The idea of tougher restrictions in the run-up to Christmas has been touted as a way to reduce infections so that family gatherings over the festive period – seen as inevitable by some – are safer.

Prof Edmunds told BBC Radio 4’s Today programme: “The idea of a lockdown is to save lives primarily.

“I think the only real way that we have a relatively safe Christmas is to get the incidence right down because otherwise I think Christmas is very difficult for people – nobody wants to have a disrupted Christmas holiday period where you can’t see your family and so on.

“So I think the only way that that can be safely achieved is to bring the incidence right down, and in order to do that we have to take action now and that action needs to be stringent, unfortunately.”

Downing Street has previously said it is the Government’s ambition to “ensure that people may celebrate Christmas as a family this year”.

In Wales, First Minister Mark Drakeford has said the current “firebreak” restrictions should give a pathway to Christmas “without needing a period of this severity of restraint between now and then”.

Sir Jeremy Farrar, director of the Wellcome Trust, added: “If we can steel ourselves now for a few weeks of greater restrictions, there’s a chance we could ease up a little between Christmas and new year without the virus getting out of control. But if we’d let it continue to multiply, we’d be in a terrible situation in December.”