Portugal is in talks with the British government over its exclusion from a list of countries exempt from the coronavirus travel quarantine.
The country's prime minister, Antonio Costa, said: "The foreign minister had a long conversation with his counterpart.
"It is very important we build a confident relationship."
Last week, the government unveiled a list of more than 70 countries which holidaymakers can visit without having to self-isolate for 14 days on their return to England.
Portugal was not among them, a decision Lisbon called "absurd".
On Friday, Mr Costa tweeted a graph appearing to show the UK had a much higher number of cases per 100,000 people than the Algarve.
The Portuguese PM added: "Which is the safest place to stay? You are welcome to spend a safe holiday in Algarve! #UK #visitportugal."
Exemptions from quarantine will apply from 10 July.
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The Department for Transport said the approved destinations pose "a reduced risk to the public health of UK citizens", but the list will be kept "under constant review".
The full list is as follows: