The United States could become the global epicentre of the coronavirus outbreak, the World Health Organisation said on Tuesday, as Britain went into lockdown and Olympic organisers considered postponing the 2020 Tokyo Games.

But the Chinese province of Hubei, where the virus was first identified in December, said it would lift travel restrictions on people leaving the region as the epidemic there eases.

On the economic side, business activity collapsed from Australia and Japan to Western Europe at a record pace in March, with data for the United States later on Tuesday expected to be just as dire.

“The coronavirus outbreak represents a major external shock to the macro outlook, akin to a large-scale natural disaster,” analysts at BlackRock Investment Institute said.

WHO spokeswoman Margaret Harris said in Geneva there had been a “very large acceleration” in coronavirus infections in the United States which had the potential of becoming the new epicentre. Over the past 24 hours, 85% of new cases were from Europe and the United States, she told reporters. Of those, 40% were from the United States.

Asked whether the US could become the new epicentre, Harris said: “We are now seeing a very large acceleration in cases in the US. So it does have that potential. We cannot say that is the case yet but it does have that potential.”

Some US state and local officials have decried a lack of coordinated federal action, saying having localities act on their own has put them in competition for supplies. US President Donald Trump acknowledged the difficulty in a tweet. “The world market for face masks and ventilators is crazy. We are helping the states to get equipment, but it is not easy,” he wrote.

Confirmed coronavirus cases exceeded 3,98,000 across 196 countries and territories as of early Tuesday, according to a Reuters tally, with over 17,400 deaths linked to the virus.

Of the top 10 countries by case numbers, Italy had reported the highest fatality rate, at around 10%, which is reflective of its older population. The fatality rate globally is around 4.3%.