Another 20,964 people in Britain have tested positive for COVID-19, bringing the total number of coronavirus cases in the country to 1,787,783, according to official figures released Thursday, Trend reports citing Xinhua.
The coronavirus-related deaths in Britain rose by 516 to 63,082, the data showed.
Also on Thursday, British Health Secretary Mitt Hancock told a virtual press conference at Downing Street that mass testing will start from next week for secondary school-age children in the areas of London, Essex and Kent, which were worst impacted by the COVID-19 pandemic.
Meanwhile, all secondary schools and colleges in Wales will move to online learning from Monday, Welsh Education Minister Kirsty Williams said.
Williams said Thursday that the move, which affects the last week of term, was part of a "national effort to reduce transmission of coronavirus".
Almost half of all Welsh schools have registered zero COVID-19 cases since they opened in September.
Earlier Thursday, data from Public Health England (PHE) showed that London recorded an average infection rate of 191.8 per 100,000 people for the week between Nov. 30 and Dec. 6, the highest in England.
PHE's latest data came after London mayor Sadiq Khan warned millions of Londoners that the British capital risks moving from Tier 2 to the highest Tier 3 restrictions amid the surge in COVID-19 cases.
However, Khan says Tier 3 is "not inevitable" if Londoners stick to the restriction rules.
"We're working incredibly hard with Londoners across the city to make sure they follow the rules," he told Sky News.
"It's really important we don't undo all of the gains made. We'll kick ourselves if we go backwards over this Christmas period," he said.
England is currently under a new three-tier system of coronavirus restrictions that replaced the month-long national lockdown in England which ended on Dec. 2. The tiers system is due to be reviewed on Dec. 16.
Under the tiers system, shops are allowed to re-open across England, giving a Christmas bonanza to the struggling retail sector, but all bars and restaurants in the toughest Tier 3 areas remain closed. The system put about 98 percent of England into the highest Tier 2 and 3.
To bring life back to normal, countries such as Britain, China, Germany, Russia and the United States are racing against time to develop coronavirus vaccines.