The British public were tonight warned they must stay indoors or face a fine as the battle against coronavirus ramped up another level.
Prime Minister Boris Johnson said all shops apart from food stores and chemists must close immediately.
Meeting friends will also be banned, but one form of exercise a day will be allowed.
The lockdown will be in a place for an initial period of three weeks, Mr Johnson confirmed.
Announcing powers not seen since wartime, Mr Johnson declared: "From this evening I must give the British people a very simple instruction - you must stay at home.
"Because the critical thing we must do is stop the disease spreading between households."
People will be allowed to leave their homes for the following reasons:
- Shopping for basic necessities, as infrequently as possible
- One form of exercise a day - for example a run, walk, or cycle - alone or with members of your household
- Any medical need, to provide care or to help a vulnerable person
- Travelling to and from work, but only where this is absolutely necessary and cannot be done from home
He added: "That's all - these are the only reasons you should leave your home.
