LONDON－British Health Secretary Matt Hancock on Wednesday said more areas of East and Southeast England will be subject to the highest level of movements restrictions as he revealed that two cases of yet another variant of the coronavirus have been identified in Britain.

To curb the spread of COVID-19, Hancock said nine counties－including Sussex, Oxfordshire and Suffolk－will enter Tier Four, the top level of restrictions, from Dec 26. Bristol, Gloucestershire, Somerset, Swindon, the Isle of Wight and the New Forest are among nine designated zones that will enter Tier Three, Hancock said at a virtual news conference from Downing Street, in reference to the grading system.

Residents in Tier Four areas must stay at home, with limited exemptions. People are also urged to work from home when they can, and should not enter or leave those areas.

In disclosing the detection of another new variant of the novel coronavirus, with the two infections, Hancock said: "Both are contacts of cases who have traveled from South Africa over the past few weeks".

The latest revelation follows an announcement on Dec 14 that a variant of COVID-19 was found circulating in southern England. That strain was said to be as much as 70 percent more transmissible than the established virus, prompting a temporary shutdown in transport links.

The second variant of the virus is linked with South Africa, Hancock told the news conference. This new variant is "yet more transmissible "and the development is "highly concerning", he said.

Cases and close contacts of cases found in Britain are being quarantined, and the British government is placing "immediate restrictions" on travel from South Africa, according to Hancock.

Experts are still learning about the second variant, and "we are pretty confident that the system we have in place will help control the spread", Sky News quoted Susan Hopkins, from Public Health England, as saying.

Meanwhile, Hancock said that the government is expanding community testing yet further in areas where the rate of infection is highest.

"So we can identify people, and especially to identify the around one in three people who carry the virus without displaying any symptoms at all," he said.

A further 39,237 people in Britain tested positive for COVID-19 on Wednesday, the highest daily increase since the start of the pandemic in the country, bringing the total number of cases there to 2,149,551, official data shows.

The total of coronavirus-related deaths in Britain stands at 69,051, the data shows.

While France and Britain had reopened cross-border travel on Wednesday after a snap 48-hour ban, some countries remain closed or extended their travel bans on the UK.