British Prime Minister Boris Johnson will be back at work on Monday after being hospitalised with coronavirus earlier this month, Downing Street says.

Key points: Mr Johnson has been recovering after being admitted to intensive care earlier this month

Mr Johnson has been recovering after being admitted to intensive care earlier this month The UK death toll from COVID-19 has surpassed 20,000

The UK death toll from COVID-19 has surpassed 20,000 Car usage in the country is on the rise despite appeals for the public to stay home

Mr Johnson has been recovering from coronavirus at his country residence Chequers after spending three nights in intensive care at London's St Thomas' Hospital in early April.

The 55-year-old first revealed he had coronavirus late last month.

He was taken to hospital on April 5, before being admitted to intensive care the next day after his symptoms worsened.

Mr Johnson will take back control of a Government under pressure from the economic fallout of shutdowns aimed at curbing the spread of the highly infectious virus.

The confirmation of his return came as Britain's toll from COVID-19 passed 20,000 deaths.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 2 minutes 12 seconds 2 m 12 s Boris Johnson posted a video message on Twitter in late March saying he had developed symptoms of coronavirus

'Tragic and terrible milestone'

Interior Minister Priti Patel described the death toll as "a tragic and terrible milestone", and urged Britons to stay at home.

The British Government is facing growing criticism over its response to the new coronavirus pandemic as the death toll rises.

The UK was slower to impose a lockdown than its European neighbours and is struggling to raise its testing capacity.

The country now has the fifth-highest official coronavirus death toll in the world, after the United States, Italy, Spain and France, and scientists have said the death rate would only start to decline quickly in another couple of weeks.

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In mid-March, the Government's chief scientific adviser said keeping the death toll below 20,000 would be a "good outcome".

The latest daily death toll of 813 hospital deaths brought the number of people who had tested positive for the illness and died in hospital to 20,319.

Car usage on the rise

Ms Patel said the country was not out of the woods yet, pleading with Britons to stay at home as more people start ignoring lockdown advice.

Data showed car usage had started to rise this week.

"Our instruction remains clear, people should stay at home, protect the NHS [National Health Service] and save lives," Ms Patel said.

"We know that people are frustrated but we are not out of danger. It is imperative that we continue to follow the rules."

Britain's total number of deaths is likely to be thousands higher with the addition of more comprehensive but lagging figures that include deaths in care homes.

As of April 10, the hospital toll was short of the overall toll by about 40 per cent.

In Mr Johnson's absence, government ministers have been struggling to explain high death rates, limited testing and shortages of protective equipment for medical workers and carers.

Health ministry data shows 28,760 tests were carried out on April 24.

That is likely to put further pressure on the Government given it had set a target of hitting 100,000 tests per day by the end of April.

Asked at the news conference when care home deaths would peak, Stephen Powis, the medical director of the NHS, declined to predict a date, but said the care sector would benefit from more testing.

There are concerns that limited testing could mean a slow exit from lockdown and a worse hit for Britain's economy, the world's fifth largest.

Earlier on Saturday, Mr Powis declined to give a new number for how many deaths could now be expected.

"It will take some time, it may take many years, before the full effect of the pandemic is known in this country," he told BBC Radio.

Striking a positive note, Mr Powis added the NHS had not been overwhelmed in the way that hospitals in some other countries had been.

Healthcare providers were preparing to ramp up non-coronavirus treatments, such as restarting planned surgeries.

"As we are now beginning to see a decline, a decrease, in the number of patients with coronavirus, it is absolutely the time to start building up our services again," he said.