Hong Kong will ban non-residents from entering the city from Japan, Portugal and Sweden from Friday, adding to a fast-expanding list of countries facing travel restrictions due to concerns over the Omicron coronavirus variant.

Non-Hong Kong residents who have been in the three countries in the past 21 days will not be allowed to enter the global financial hub.

Residents can only board flights if fully vaccinated and will have to undergo 21-days of quarantine in a hotel at their own cost, Reuters reported.

The government's late Tuesday announcement adds to a growing list of countries facing similar restrictions