The World Health Organisation (WHO) has appealed to people to stay home during the holiday season as it is “not worth the risk” of catching Covid-19.

With more than two-thirds of England’s population to be living under Tier 3 measures from Saturday as the UK Government tries to stem rising infections, WHO said “the safest thing to do right now is to remain at home”.

The organisation’s regional director for Europe Dr Hans Kluge said: “There remains a difference between what you are being permitted to do by your authorities and what you should do.”

In a statement, he said: “We have a few more months of sacrifice ahead and can behave now in a way that collectively we are proud of. When we look back at these unprecedented times, I hope we all felt we acted with a spirit of shared humanity to protect those in need.”

It comes as Dame Donna Kinnair, chief executive and general secretary of the Royal College of Nursing, warned relaxing coronavirus restrictions over Christmas could lead to an “unrelenting tsunami” of cases.

“After a difficult year, it is everybody’s instinct to want to be together and see loved ones – especially those who live far apart or feel isolated. But what is at stake is coming into sharp focus,” she said.

“Travelling and family visits associated with this time of year will undoubtedly lead to more cases, more pressure on NHS and care services, and more deaths. By turning the second and third waves into an unrelenting tsunami, we would begin 2021 in the worst possible way.”

She said nurses would not enjoy Christmas “knowing what awaits them in January” and called on the Government to be “clearer about the risks – not just the rules”, warning: “This virus isn’t taking Christmas off and nor should we.”

Dr Kluge said the pandemic’s “devastation” had hit communities across Europe.

“Covid-19 has forced families and communities apart, bankrupted businesses, and deprived people of opportunities that a year ago were taken for granted,” he said.

“From anxieties around virus transmission, the psychological impact of lockdowns and self-isolation, to the effects of unemployment, financial worries and social exclusion – the mental health impact of the pandemic will be long term and far reaching.

“What has resulted is a growing mental health crisis in Europe.”