The Nehru Centre in London, the cultural wing of the Indian High Commission, is suspending its functions, initially until April 15, because of the coronavirus pandemic.

The decision coincided with a grim warning from the British Prime Minister Boris Johnson about the disease: “It is going to spread further and I must level with you, I must level with the British public: many more families are going to lose loved ones before their time.”

Johnson made his comments at 10 Downing Street, on Thursday, following a meeting of the government’s emergency committee with the acronym, Cobra.

Flanked by his leading advisers on the crisis — Patrick Vallance, the UK’s chief scientific adviser, and Prof. Chris Whitty, chief medical officer for England — Johnson said: “We’ve all got to be clear: this is the worst public health crisis for a generation.”

French President Emmanuel Macron has gone further and declared the pandemic as France’s worst health crisis in a century and announced schools, universities and day-care centres would be shut from Monday.

In the UK, although nearly 600 people have tested positive for the virus and 10 have died, between 5,000 and 10,000 people are thought to be infected with Covid-19 already, according to Valance.

Johnson said that from now on, people with even mild coronavirus symptoms, including a continuous cough or high temperature, must stay at home for at least seven days. School trips abroad should be stopped, people over 70 with serious medical conditions are being told not to go on cruises, and officials warned the advice is likely to develop so that entire households could be told to self-isolate.

Johnson insisted comparisons to seasonal flu were wrong. “This is more dangerous.”

But his health advisers have said it would be counterproductive and premature to close schools and colleges and ban large gatherings.

Whitty said the peak of the outbreak is most likely still 10 to 14 weeks away. He said it is feared people will become “fatigued” by more stringent measures if they are brought in too soon and therefore they would lose their maximum effect. Health secretary Matt Hancock also tweeted: “We will base our decisions on the bedrock of the science — and do the right thing at the right time to keep people safe.”

Ireland, which shares a land border with the UK, announced the closure of all schools and childcare facilities and other public spaces such as museums, while Scotland banned gatherings of more than 500 people.

Johnson has come under fire for not taking similar action, notably from Jeremy Hunt, the former health and foreign secretary, whom he defeated last year in the Tory leadership contest.

Hunt told the BBC: “I think it is surprising and concerning that we’re not doing any of it at all when we have just four weeks before we get to the stage that Italy is at.”

Portuguese Prime Minister Antonio Costa ordered the shut-down of schools and universities and placed limits on the number of people in nightclubs, restaurants and shopping centres at any one time;

Belgium announced the closure of all schools, restaurants, cafes and nightclubs and also banned recreational and sporting events in its fight to contain the growing epidemic.

Danish authorities called on shoppers to avoid excessive stockpiling after it closed schools and universities and suspended indoor events with more than 100 participants;

Germany shut nightclubs and schools after Chancellor Angela Merkel warned that up to 58 million people in a population of 83 million — 70 per cent — could contract the coronavirus.

Johnson has discussed international cooperation to combat the disease in a telephone conversation with Narendra Modi.