Portugal has been downgraded to the amber list, ruining the plans of thousands of British holidaymakers.
It was added to the green list on 7 May, and tour operators and airlines piled on capacity to cater to a surge in demand.
Arrivals from Portugal will be required to self-isolate at home for 10 days.
Transport secretary Grant Shapps announced the downgrade of the Atlantic nation, a holiday favourite of British travellers.
He added that the UK’s “first priority” was the “domestic unlocking”, urging holidaymakers to have “a little bit of patience”.
In an interview, Mr Shapps has raised concern of a so-called Nepal coronavirus mutation in Portugal as it was taken off the green travel list.
He said: “I want to be straight with people, it’s actually a difficult decision to make, but in the end we’ve seen two things really which caused concern.
“One is the positivity rate has nearly doubled since the last review in Portugal and the other is there’s a sort of Nepal mutation of the so-called Indian variant which has been detected and we just don’t know the potential for that to be vaccine-defeating mutation and simply don’t want to take the risk as we come up to June 21 and the review of the fourth stage of the unlock.”
Additional reporting by agencies
