Britain has ordered a three-week lockdown to tackle the spread of coronavirus, shutting "non-essential" shops and services, and banning gatherings of more than two people.
"Stay at home," Prime Minister Boris Johnson said in a televised address to the nation on Monday, as he unveiled unprecedented peacetime measures after the country's death toll climbed to 335.
The announcement came after outrage in government that recommendations about reducing social contact to minimise close-contact transmission of the virus were being ignored.
Crowds of people were seen enjoying weekend spring sunshine in parks and countryside across the country, prompting calls for tougher action to be imposed.
"From this evening (Monday) I must give the British people a very simple instruction -- you must stay at home," Johnson said.
"Because the critical thing we must do is stop the disease spreading between households." Under the new measures, Johnson said going out to shop for basic necessities was still allowed, as was exercise, medical need, and travel to and from work.
But shops selling items such as clothes or electronics, libraries, playgrounds and places of worship would be shut, with a ban also extending to weddings and baptisms but not funerals.
Parks will remain open but Johnson warned: "If you don't follow the rules the police will have the powers to enforce them, including through fines and dispersing gatherings."