The UK has reached “a perilous turning point”, Prime Minister Boris Johnson has says, as he set out a raft of new Coronavirus restrictions for England which could last for up to six months.
Shop staff will have to wear face masks and weddings will be limited to a maximum of 15 people, under the rules.
Fines for breaking laws on gatherings and not wearing a mask will increase to £200 for a first offence.
He also warned “significantly greater restrictions” could come if necessary.
Mr Johnson said “similar steps” would be taken across the UK after he met with the leaders of Scotland, Wales and Northern Ireland on Tuesday morning.
Like England, Scotland’s First Minister, Nicola Sturgeon, also announced a 22:00 curfew for hospitality businesses. The same measure is also set to come into force in Wales on Thursday.
Ms Sturgeon went further than England on restrictions, banning the visiting of other households indoors.
It comes as the number of UK cases rose by 4,926 on Tuesday, government figures showed, with deaths increasing by 37.