Countries were racing to contain the Omicron coronavirus variant by restricting travel and imposing new quarantine measures as new cases were detected around the world on Sunday.

A third case was identified in the UK and dozens more were being treated as suspected cases, people familiar with the matter told the Financial Times. The government mandated mask-wearing for shops and public transport in England, and people entering the UK will be required to take a PCR test within two days of their arrival and self-isolate until they receive a negative result.

The US, the European Union, the UK, Australia, Saudi Arabia, South Korea all limited travel or ordered quarantines on individuals travelling to and from southern Africa, while others, such as Singapore and India, signalled they were reviewing restrictions. Switzerland has also restricted travel to non-African nations where cases have been detected.