Omicron spreads to more countries, China warns of ‘challenges’ for Winter Olympics

China warned Tuesday that the fast-spreading Omicron Covid-19 variant would cause challenges in hosting next February's Winter Olympics in Beijing.

Although China has largely quashed the coronavirus within its borders through travel restrictions and snap lockdowns, recurrent domestic outbreaks linked to the Delta variant have put the authorities on high alert.

"I think it will definitely lead to challenges linked to prevention and control," foreign ministry spokesman Zhao Lijian said, adding that Beijing "appreciates the efforts by South Africa in offering timely information" on the variant.

"But China has a lot of experience in responding to Covid-19," Zhao added. "I firmly believe the Winter Olympics will be conducted smoothly."

China is determined to pull off a smooth Olympic Games unmarred by Covid-19, in what would be a decisive propaganda win for Beijing's zero-tolerance Covid strategy.

Thousands of athletes, media and participants arriving from overseas are required to enter a strict "closed-loop" bubble.

Organisers last month admitted that the virus would be the "biggest challenge" in hosting the Games.

But health authorities said they had the means to cope with the new variant.

"China has already done a good job of technical preparations" for the Omicron variant, said Xu Wenbo, head of the virus control institute at China's Centre for Disease Control and Prevention.

"We have many lines of technical research, including preliminary technical research into deactivated vaccines, protein-based vaccines and vector-based vaccines," he said at a separate Tuesday briefing.

More than 1.1 billion people have been fully vaccinated against the coronavirus as of Monday, according to health authorities.