The Hong Kong government imposed an entry ban on travelers from five additional countries, including South Korea, following the emergence of the new omicron variant of COVID-19.

Authorities in Hong Kong said on Friday that the entry ban will be implemented as of 12:00 a.m. Sunday for the five countries that have reported the variant: South Korea, Finland, Saudi Arabia, Norway and Ghana.

Hong Kong residents who are returning from one of the five countries can only board flights bound for Hong Kong if they have been fully vaccinated. Upon arrival, they will undergo a three-week quarantine at a state facility or a hotel.

Starting Wednesday, travelers transferring flights in Hong Kong will be required to submit a document proving that they tested negative in a PCR test within the previous 72 hours.

Hong Kong has so far confirmed four cases of the new variant.