The UK has recorded the highest one-day rise in coronavirus cases since May in the past 24 hours, government figures show.
Some 3,991 people tested positive, bringing the total number of current UK cases to 378,219.
Another 20 deaths within 28 days of a positive test were reported, as of 9am on Wednesday. It makes the official death toll 41,684.
The number of people in hospital suffering Covid-19 is 901, up by 141 in 24 hours.
Separate figures published by the UK's statistics agencies show there have now been 57,500 deaths registered in the UK where Covid-19 was mentioned on the death certificate.
The sharp rise in cases comes as people continue to struggle to get tests.
Tests were not available for people with coronavirus symptoms in some of England's worst affected areas on Wednesday. It was not possible to book a test in Bolton - which currently has the highest infection rate in England - on Wednesday morning, as the testing system struggles to cope with soaring demand.