The government is under pressure to explain how it will meet its target of increasing coronavirus testing ten-fold by the end of April.
Health Secretary Matt Hancock has said he wants 100,000 tests to be carried out every day.
But Labour said there were no details on how this could be achieved and what sort of testing would be involved.
It comes as a field hospital with capacity for up to 4,000 patients is to be opened in east London.
London’s new NHS Nightingale Hospital will treat intensive care Covid-19 patients in the temporary facility at the ExCel convention centre.
Speaking on Thursday at the Downing Street coronavirus briefing, following days of criticism of the government’s record on testing, Mr Hancock announced a “five-pillar” plan to reach the 100,000 target.
- Swab tests – to check if people already have the virus – in labs run by Public Health England
- Using commercial partners such as universities and private businesses like Amazon and Boots to do more swab testing
- Introducing new antibody blood tests to check whether people have had the virus in the past
- Surveillance to determine the rate of infection and how it is spreading across the country
- Building a British diagnostics industry, with help from pharmaceutical giants
Labour MP Yvette Cooper, who chairs the Commons home affairs committee, told BBC’s Question Time the target was welcome but a “centralised approach” with all tests being carried out by Public Health England would be “just not enough” to meet demand.
Shadow health secretary Jonathan Ashworth called for more clarity and details, asking how many of the 100,000 tests would be blood tests, and what role testing will play in the government’s “exit strategy” to end the lockdown.
David McCoy, professor of global public health at Queen Mary University, said the government’s pledge was “a step in the right direction”, but cautioned that testing was not a “magic bullet”.
He also called for a less “centralised, top down uniform” approach by the government, saying the epidemic was at different stages across the country and required a more regional approach with greater emphasis on local plans.
Figures released on Thursday showed the number of people with the virus who have died in the UK had risen by 569, taking the total to 2,921 as of 17:00 BST on Wednesday.
On Wednesday, there was capacity for 12,799 daily tests in England – although just 10,650 people were tested. The government’s target by mid-April had been to test 25,000 per day.
Latest figures show 163,194 people in the UK have so far been tested for the virus, of which 33,718 were confirmed positive.
Doubt has also been cast on the idea of “immunity certificates” being given to people who have recovered from coronavirus.
On Thursday, Mr Hancock, who was making his first public appearance since going into self-isolation after contracting coronavirus, said the government was considering the idea to allow people to “get back, as much as possible, to normal life”.
He added that it was “too early in the science” to give further details.
But Eleanor Riley, professor of immunology and infectious disease at the University of Edinburgh, said such certificates would give people a “sense of false security” about the disease.
“It’s not something that we’ve ever done before,” she said.
“When we vaccinate people, particularly for certain diseases where they’re going to travel overseas… we give people a certificate saying they have been vaccinated.
“But that certificate doesn’t say they are immune and there’s a difference. We don’t know yet whether somebody who has had this virus is immune.
“They have antibodies, they’ve clearly been exposed, yet will those antibodies protect them against re-infection? I’m not sure that we know that.”
Meanwhile, the new Nightingale hospital will officially open later – less than two weeks after military personnel, working with NHS managers and clinicians, began transforming the Excel conference and exhibition centre into a giant hospital.
The facility, which normally plays host to lifestyle shows, expos and conferences, will be split into more than 80 wards containing 42 beds each and will be one of the biggest hospitals in the world, according to its chief operating officer, Natalie Forrest.
Mr Hancock said the NHS and the military had “achieved something extraordinary” in setting up the hospital in “only a matter of days”.
It comes as NHS England announced two more temporary hospitals will be built in Bristol and Harrogate to cope with an expected surge in coronavirus patients in the next few weeks.
Plans to use conference centres in Manchester and Birmingham have already been announced.
In other developments:
- Heathrow will close one of its runways next week as air traffic continues to fall globally amid the coronavirus pandemic
- Donna Kinnair, chief executive of the Royal College of Nursing, told BBC Newsnight they had been urging the government “for weeks” to make ordering personal protective equipment (PPE) for NHS workers a priority
- The government is writing off £13.4bn of historic NHS debt, so that hospital trusts are in a “stronger position” to deal with the outbreak
- Premier League footballers should take a pay cut to help the UK respond to the crisis, Mr Hancock said, adding that: “Everyone needs to play their part.” It comes after some clubs were criticised for using a government scheme to cut the salaries of non-playing staff, while paying players in full
- Public Health England has updated its guidance on when staff should wear personal protective equipment