Britain's official coronavirus death toll is now over 40,000 with almost 10,000 dead in care homes in England and Wales alone, according to a statistical update released on Tuesday.

A sign on a platform advises passengers to adhere to social distancing at Waterloo Train station in central London on May 18, 2020. (Photo: AFP)

Some 40,902 deaths from coronavirus were registered by May 8, according to the Office for National Statistics (ONS), meaning the true toll will be even higher when deaths registered over the last 10 days are taken into account.

The ONS figures include deaths where COVID-19 is suspected or mentioned on the death certificate.

The government's official rolling tally, which was 34,796 as of Monday, is lower because it only records deaths after positive tests.

Either way, Britain is the worst-hit country in Europe, and the government has been criticised heavily for its response to the outbreak.

The ONS figures show a sharp fall in coronavirus deaths in the week up to May 8, reinforcing ministers' claims that the country is past the peak.

Numbers in England and Wales fell from 6,035 to 3,930. Care home deaths accounted for 42.4 percent of the total -- up from 40.4 percent the week before.

Deaths in care homes fell at a slower rate than the population at large, and the total number of deaths in care homes in England and Wales now stands at 9,975.

A cross-party parliamentary committee looking into the government's handling of the crisis on Tuesday said testing had been "inadequate" in a letter to Prime Minister Boris Johnson.

"The decision to pursue an approach of initially concentrating testing in a limited number of laboratories and to expand them gradually... is one of the most consequential made during this crisis," they said.

"From it followed the decision on March 12 to cease testing in the community and retreat to testing principally within hospitals."

The decision meant residents in care homes could not get tests when the virus was at its most potent stage, they added.