Britain's decision to suspend flights from Portugal because of concerns about a new coronavirus strain in Brazil is "absurd", Portuguese Foreign Minister Augusto Santos Silva said.
Santos Silva told the state-owned news agency Lusa late on Thursday he had requested a meeting with British foreign minister Dominic Raab to clarify the situation.
Britain's transport minister announced on Thursday that Portugal had been added to a list of South American countries from which arrivals were being banned because of its close travel links to Brazil.
"This is an absurd measure, and we don't understand what it is based on," Santos Silva said.
There is no evidence that the Brazilian strain is present in Portugal, according to health authorities.
Flights between Portugal and Brazil remain available as part of a wider Portuguese policy of maintaining travel to countries with large Portuguese diasporas. The policy allows only essential travel and does not include tourism.
Travellers must present a negative coronavirus test taken up to 72 hours before departure.
Santos Silva criticised the short notice given by Britain for the new measure, which went into force at 0400 GMT on Friday.
He said Portugal had not banned travel from Britain when a new strain of the coronavirus was first identified in the United Kingdom, but had followed European Union policy by simply requiring a negative coronavirus test from travellers.
"I believe in the value of reciprocity," he said.