Britain has made it mandatory for UK residents and nationals arriving from more than 30 countries to enter 10 days supervised quarantine in hotels, beginning from Feb.15.
The measure was intended to prevent the spread of new variants of the novel coronavirus, the Ministry of Health in London said in a statement early on Friday.
Portugal, all states in South America and southern Africa, and the United Arab Emirates will be affected.
Arrivals from other countries must isolate privately for 10 days, as was the previous policy.
The new measure is aimed primarily at British travellers returning to the country.
Entry from these countries were already banned for people not resident in the United Kingdom.
Prime Minister Boris Johnson had flagged the move some time ago, but had not given a specific date for the policy’s start.
The opposition Labour party said it was beyond comprehension that the government waited so long to implement the measure.
The ministry said it was working at pace to secure the facilities it needed.
The hotel industry agreed to cooperate, while the airline industry sharply criticised the plan.
Quarantine hotels are expected to be set up near airports including Heathrow, Gatwick, London City, Birmingham, Bristol, Manchester, Edinburgh, Glasgow and Aberdeen, the BBC reported.