Abu Dhabi has removed the UK from its green list of travel destinations.
The decision means unvaccinated passengers from the UK must quarantine in a residence or hotel for 10 days on arrival in Abu Dhabi.
Vaccinated passengers from non-green list countries are tested on arrival and six days later. They are not required to quarantine.
The test-on-arrival at Abu Dhabi airport is free, and the day six test is free in any clinic run by the public hospital group Seha.
The updated list, which is effective from Monday, January 3, comes after a surge in Covid-19 cases in many countries, largely tied to the Omicron variant.
Dubai has separate rules, including testing on arrival from some destinations. It requires only people who test positive to quarantine.
On Saturday, the UAE government said it will ban unvaccinated Emiratis from travelling abroad from January 10. The decision was not extended to expats.
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Updated Abu Dhabi green list includes:
Albania
Algeria
Armenia
Australia
Austria
Azerbaijan
Bahrain
Belarus
Belgium
Bosnia and Herzegovina
Brazil
Bulgaria
Burma
Cambodia
Canada
China
Croatia
Cyprus
Czech Republic
Denmark
Finland
France
Georgia
Germany
Greece
Hong Kong (SAR)
Hungary
Indonesia
Iran
Iraq
Israel
Italy
Japan
Kazakhstan
Kuwait
Kyrgyzstan
Laos
Latvia
Luxembourg
Malaysia
Maldives
Morocco
Netherlands
Norway
Oman
Papua New Guinea
Philippines
Poland
Portugal
Romania
Republic of Ireland
Saudi Arabia
Serbia
Seychelles
Singapore
Slovakia
Slovenia
South Korea
Spain
Sweden
Switzerland
Syria
Taiwan, Province of China
Tajikistan
Thailand
Tunisia
Turkmenistan
Ukraine
United States of America
Uzbekistan
Yemen