The number of coronavirus deaths in Britain jumped on Tuesday, the first day of a national lockdown, while the government called for 250 000 volunteers for the health service and announced a temporary hospital would open in London next week.

In a television message on Monday evening watched by more than 27 million people, Prime Minister Boris Johnson ordered people to stay at home, told nearly all shops to close and banned social gatherings including weddings and baptisms.

However, public transport in London was busy during the morning rush hour and the streets were far from deserted amid confusion over the government’s advice to workers.

The death toll from coronavirus in the United Kingdom has jumped by 87 to a total of 422 – the biggest daily increase since the crisis began.

Meanwhile, the economic devastation was underscored by a survey that suggested the economy was shrinking at a record pace, faster than during the 2008-09 financial crisis.

The unprecedented peacetime restrictions announced by Johnson, which will last at least three weeks, are intended to stop the state-run National Health Service (NHS), which suffers from staff shortages at the best of times, being overwhelmed.

“These measures are not advice, they are rules and will be enforced, including by the police,” health minister Matt Hancock told parliament.

At a news conference later, Hancock announced plans to open a temporary hospital next week at the Excel Centre, a huge venue in east London normally used for trade fairs and similar events.