Britain added seven countries, including Egypt and Sri Lanka, to its “red list” of destinations that require hotel quarantine on return to England on Thursday, in a review that also saw Portugal move from “green” to “amber”.

Britain added seven countries — Afghanistan, Bahrain, Costa Rica, Egypt, Sri Lanka, Sudan and Trinidad and Tobago — to its “red list” of places with severe COVID-19 outbreaks. 

All but essential travel to red list countries is barred, and U.K. residents returning from any of them must spend 10 days in a government-approved quarantine hotel.

No countries were added to the quarantine-free green list.

The full list of countries added to the “red list” is: Afghanistan, Bahrain, Costa Rica, Egypt, Sri Lanka, Sudan, and Trinidad & Tobago.

Britain said that it is removing Portugal from its list of COVID-safe travel destinations, meaning thousands of U.K. residents currently on vacation there face the prospect of 10 days’ quarantine on return.

Transport Secretary Grant Shapps said the “difficult decision” was prompted by rising infection rates in Portugal and worries about new versions of the coronavirus that could prove resistant to vaccines. He said a mutation of the delta variant first identified in India was causing particular concern.

He said “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 a vaccine-defeating mutation and simply don’t want to take the risk as we come up to June 21” — the date the U.K. government hopes to lift remaining coronavirus restrictions.

The U.K. has recorded almost 128,000 coronavirus deaths, the highest toll in Europe. A mass vaccination campaign that started in December has given two doses of vaccine to more than half the adult population and brought new infections and deaths down sharply.

But case numbers are once again rising as the more transmissible delta variant spreads across the U.K.

-Agencies