This 2019 file photo shows the apron of the Hong Kong International Airport. (PHOTO/HKSAR GOVERNMENT)

Hong Kong will implement what the city calls its most stringent quarantine and testing requirements for inbound travelers from the US after an imported Omicron case was detected from there.

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Hong Kong also added Cuba, Kuwait and Liechtenstein to its Group A list from 12 am Monday. That means such arrivals will need to do 21 days of hotel quarantine

Hong Kong residents who have stayed in the US within 21 days of arrival will be required to undergo compulsory quarantine at the Penny’s Bay center for the first week, according to a statement Friday night. They would then be transferred by designated transport to serve their remaining 14 days of compulsory quarantine at designated hotels the travelers had already reserved. US arrivals were already subject to three weeks of quarantine, all of it served in hotels.

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The change, which will apply to those arriving starting 12 am Monday, follows a visitor arriving from the US testing positive under the “test-and-hold” arrangement at Hong Kong’s airport, the statement. Arrivals from 12 African countries already have to spend their first week at Penny’s Bay. Everyone there is tested daily for COVID-19.

Meanwhile, Hong Kong added Cuba, Kuwait and Liechtenstein to its Group A list from 12 am Monday. That means such arrivals will need to do 21 days of hotel quarantine. They joined more than 30 countries into its high-risk category the past two weeks due to Omicron, a COVID-19 variant first reported in South Africa on Nov 24. Only Hong Kong residents are allowed to travel from the high-risk places, with visitors banned.