British Prime Minister Boris Johnson will set out his plan to ease a nationwide coronavirus lockdown next Sunday, media reports said, as new guidance emerged on how to maintain social distancing in workplaces.

Stay-at-home orders imposed in late March are up for review on Thursday in the UK, one of the worst-hit countries in the Covid-19 pandemic, but the government has already said the measures will be eased only gradually.

New guidance drawn up with company bosses and trade unions, seen by the BBC and the Financial Times, suggests office workers will be encouraged to stay at home for months to avoid overwhelming the transport system.

But where staff must come in, companies are being urged to stagger shifts, stop people sharing desks or stationery, step up hygiene measures, keep staff canteens shut and restrict the number of people in lifts.

Shop or bank branch workers dealing with customers must be protected by plastic screens, according to the recommendations, although there is no detail on what kind of protective equipment other employees might require.

Britons are currently being told to stay at home unless they need to work, buy essentials or take daily exercise, but they must stay at least two metres away from other people.

Maintaining this social distancing while restarting the economy brings huge problems.

"It won't work in aviation or any other form of public transport, and the problem is not the plane, it is the lack of space in the airport," said the chief executive of London's Heathrow Airport, John Holland-Kaye.

"Just one jumbo jet would require a queue a kilometre long," he wrote in the Daily Telegraph.

The Covid-19 death toll has risen by 288 to 28,734, according to figures announced today by Health Secretary Matt Hancock.

The increase is the smallest since late March, Mr Hancock said, adding that he expected the figure to rise in coming days as the numbers tended to be lower during the weekend.

Mr Johnson has warned that lifting lockdown restrictions too soon would be "the worst thing we could do".

In a video message on Twitter, the prime minister said it was important to meet the five tests set by the government before easing the lockdown.

"We will only be able to move onto the second phase of this conflict if our five tests have been met," he said.