Britain on Thursday said another 616 people had died in hospital from the novel coronavirus, as the government detailed a new testing regime that could allow the country to ease its lockdown.

The latest death count -- recorded in the 24 hours to 1600 GMT on Wednesday -- was lower than the 759 from the previous day and follows other signs the virus may have hit its peak.

It takes Britain's hospital death toll to 18,738, according to the health ministry.

The actual number of deaths from the COVID-19 illness is likely to be far higher once officials count fatalities at care homes and in the community, which take longer to be included in the official statistics.

Britain remains one of the worst-hit by the pandemic and has been under stringent social distancing rules for a month.

The government has been criticised for its response to the outbreak, with claims it was slow to impose restrictions and introduce widespread testing.

Health officials have also faced repeated questions about the supply of personal protective equipment to frontline health and social care workers dealing with virus patients.

The government is under growing pressure to explain how it will lift the lockdown, which has led to the economy grinding to a virtual halt.

Scotland's First Minister Nicola Sturgeon published her devolved government's plans on Thursday, saying they could be eased in a phased manner north of the border with England.

But British health minister Matt Hancock again refused to disclose the UK government's proposals at the daily Downing Street briefing.

He instead detailed expanded testing for the virus in the coming weeks, following criticism of the country's sluggish sampling and a failure to use the growing available capacity.

"Our ultimate goal is that everyone who could benefit from a test gets a test," Hancock said.

'Test, track, trace' 

Hancock vowed earlier this month that 100,000 tests would be carried out every day by the end of April, and insisted the target would be met.

Capacity for testing was currently at 51,000 tests per day, he told reporters.

He said the government would now make it "easier, faster and simpler" for so-called essential workers to get tested, through an online booking system, and expanded regional and mobile sampling sites. 

Meanwhile, it will reintroduce within weeks a "test, track and trace" strategy, which was first used at the outset of the outbreak before it became uncontrollable.

Health officials are hiring 18,000 people, including 3,000 clinicians, to spearhead the scheme.

"This test, track and trace will be vital to stop a second peak of the virus," Hancock said.

But he warned there was "no automatic link" between the programme's rollout and lifting the lockdown, which would be contingent on lower rates of transmission and other factors.

"You've got to get it down first for test, track and trace to be effective," he added.

Britain's chief medical officer Chris Whitty warned on Wednesday that some of the tough social distancing measures could be in place for the rest of the year until a vaccine is found.

Oxford University began a human trial of a potential coronavirus vaccine on Thursday, with the aim of making it available to the public later this year if successful.

The university is also involved in a nationwide survey with the Office for National Statistics of 25,000 people to determine the extent of the virus' spread in the community.

The scheme is expected to be expanded to up to 300,000 people in 12 months to help deepen scientific understanding of the virus, Hancock said.