Working on Christmas Day is likely for those leading the effort to tackle coronavirus, as the threat posed by the Omicron variant increased, England’s chief medical officer has said.

Professor Chris Whitty said the situation was “pretty depressing” to think about the gaps on rotas that would be seen in the health service, and that he expected his plans to be cancelled.

Boris Johnson said he has “pretty modest” arrangements, adding: “I think the way things are looking I expect a lot of us are going to be working throughout the period.”

It comes as Prof Whitty urged people to deprioritise some social interactions in order to make sure the meetings they wanted to keep could be met.

He said it was likely his Christmas plans this year with family will be interrupted.

He told a Downing Street press conference: “Realistically, I think there’s a high chance that my original Christmas plans with family are going to be interrupted. I hope it’s not completely but we shall see.”

He said the expected sharp peak of Omicron cases is likely to lead to lots of people, including healthcare workers, being ill at the same time.

He said: “We may end up with quite substantial gaps in rotas at short notice.”

He added: “Given how much difficulty my health and social care colleagues have had over the last two years, saying that is pretty depressing, because they have really, really had to stand up and go back again and again.

“The reality is this speed of onset is going to lead to lots of people getting ill simultaneously and we have to be realistic about that.”

Dr Nikki Kanani, medical director of primary care for NHS England, apologised to her children live on television for their scaled-back plans in the run-up to Christmas.

She said: “As for my Christmas plans, they’re already scaling back. There will be far fewer things that I’ll do with my children as we run-up to Christmas – and if they’re listening, sorry, but that is absolutely a fact.

“We will enjoy it together, we will enjoy it at home and we will enjoy it safely.

“As and when I need to work over the Christmas period I will be, just as my colleagues will be, because that’s what we’re here to do.”