Burundi and Rwanda have been added to the “red list” of countries from where travel to the UK is banned.
The measure, aimed at stopping the spread of the South African variant, comes into force starting today.
British, Irish and third country nationals with residence rights in the UK will be allowed to enter but must self-isolate for 10 days at home.
UK Transport Secretary Grant Shapps said passengers allowed to enter the country would need proof of a negative test and a completed passenger locator form before arrival, or could face £500 fines.