Moving Portugal off the UK’s green list is “an overreaction”, an epidemiologist in the popular holiday destination has claimed.

Professor Henrique Barros, president of Portugal’s National Health Council, said the country’s overall coronavirus situation is “relatively stable”.

He made the comments after Communities Secretary Robert Jenrick said positive cases had doubled in the last three weeks in Portugal.

Prof Barros told Sky News: “We didn’t reach such an increase, except as I said in a specific area around Lisbon.

“The overall picture in the country, we didn’t reach such figures.”

The decision to move Portugal to the amber list means people returning to the UK from there must self-isolate at home for 10 days.

“I think it’s an overreaction,” Prof Barros said.

The health chief explained that the rise in infections are mainly among people aged under 40, and there is a “very low incidence of cases” in the over-50s.

He stressed that hospital admissions at the present time are “very low”, at less than 25 people per million.

Officials in the country “pay a lot of attention” to monitoring the virus, he added.

Mr Jenrick acknowledged that the situation was “frustrating” for travellers, but insisted the Government was “clear” that the classification of green list countries could change.

“Those countries are being reviewed every three weeks, and so there was always a risk with a fast-moving situation with new variants that countries might either go on to that list, or indeed come off,” he told Sky News.

The Cabinet minister said the movement of Portugal to the amber tier was partly due to “growing evidence of a further mutation being called the Nepal variant”.

He revealed “we don’t yet know how much of a problem that is” but insisted it is “important that we take a cautious approach”.

Julia Lo Bue-Said, chief executive of travel agent group Advantage Travel Partnership, said the decision in relation to Portugal was “an absolute devastating blow” for consumers and the industry.

She told BBC Radio 4’s Today programme: “It now throws confidence completely out of the window.”

She added: “It puts the industry in a really difficult position and consumers in a difficult position in order to be able to plan effectively.”

Tim Hawkins, chief strategy officer at Manchester Airports Group, which owns Manchester, Stansted and East Midlands airports, claimed the Government “isn’t willing to take any risk at all”, and urged ministers to “trust in the traffic light system”.

He told Times Radio: “For people coming back from green countries you have to take a pre-departure test, you have to take a test when you come back.

“There is not a free flow of people coming back from those countries.

“There are safeguards, there are measures in place to control those kinds of things, but the Government seems to have ignored those.”

Portugal is not the only country that has moved on the traffic light rating system.

Afghanistan, Bahrain, Costa Rica, Sudan, and Trinidad and Tobago have also been placed on the red list, meaning people arriving in the UK from those nations must stay in a quarantine hotel for 11 nights.

The changes come into effect at 4am on Tuesday.