Like other European countries, Britain has seen a second wave of coronavirus infections since pubs and restaurants reopened, children went back to school and students returned to university.
Five areas with high infection rates, including the biggest cities of Glasgow and Edinburgh, face further measures including a takeaway-only rule for bars and a recommendation to avoid public transport.
Last week, the government announced that nearly 16,000 new coronavirus infections had gone unreported as a result of a technical glitch, leading to delays in tracking down contacts.
A total of 3,145 coronavirus patients were in U.K. hospitals on Tuesday, up from 2,390 a week earlier.
Both figures are well below the peaks seen at the height of the U.K. outbreak in the spring.