Britain has recorded its highest daily number of coronavirus cases since May.
2,988 new cases were announced on Sunday. This follows a pattern across European countries, where case numbers are rising as society opens up again after lockdown.
The number of hospital admissions and deaths has so far not shown a corresponding rise however, with two new deaths reported on Sunday.
UK Health Secretary Matt Hancock described the rise of new virus cases as "concerning," saying that the government will keep instituting local lockdowns if needed.
He urged people to keep respecting social distancing regulations as the ''first line of defence for everybody, no matter who you are, no matter how old you are.''
''So that we don't pass it on to people who will end up hospitalised or worse,'' he said.
The rise in COVID-19 cases comes as children go back to school.
Britain has the highest confirmed death toll in Europe, at 41,551.
Elsewhere in Europe
France recorded nearly 25,000 new cases over three days, with 7,000 new cases on Sunday following 8,500 on Saturday and 9,000 on Friday, according to the public health authority.
In Italy, former prime minister Silvio Berlusconi was responding “optimally” to COVID-19 treatment, according to his doctor, who warned that he is in “the most delicate phase” of the virus.
Dr. Alberto Zangrillo, who is head of intensive care at the San Raffaele hospital in Milan, repeated Sunday that he nevertheless remained “cautiously optimistic” about the 83-year-old’s recovery.
Worldwide, the United States remains the worst affected country in terms of deaths (188,540), followed by Brazil (126,203), India (70,626), Mexico (67,326) and the United Kingdom (41,549).