Portugal will be removed from the green travel list as Transport Secretary Grant Shapps raised concerns of a new coronavirus mutation and rising cases.

Labour criticised the “chaos” as reports about the travel restrictions dripped out of the Government on Thursday without official confirmation.

Unattributed reports suggested Portugal would be put on the amber list following a meeting between the Westminster and devolved governments, as well as the Joint Biosecurity Centre.

People returning to the UK from amber list countries must self-isolate at home for 10 days as part of coronavirus restrictions.

Meanwhile, seven countries – Afghanistan, Bahrain, Costa Rica, Egypt, Sri Lanka, Sudan, and Trinidad and Tobago – have been added to the red list.

That means people arriving in the UK from those nations will be required to stay in a quarantine hotel for 11 nights.

Mr Shapps 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.”

Many holidaymakers in Portugal face a scramble for flights home before the move is introduced, which is expected to be on Tuesday.

Shadow home secretary Nick Thomas-Symonds MP said: “The UK Government have caused chaos with the mishandling of travel restrictions at the border.

“The confusion over the ‘amber list’ has led to reports of over 50,000 people travelling to the UK daily, with only a tiny percentage going into hotel quarantine and a stream of flights entering the UK from ‘Amber List’ countries.

“Labour has warned time and time again that this is leaving the door wide open to new strains of the virus.

“Moving Portugal onto the ‘Amber List’ is not the answer. The ‘Amber List’ itself should be scrapped.”

The Government’s move is a huge blow for the travel industry, as the country was the only viable major tourist destination on the green list.

It is only 17 days since the ban on non-essential leisure travel from Britain was lifted.

Portugal’s seven-day rate of coronavirus cases per 100,000 people stands at 37.2, up from 30.7 a week earlier.

The PA news agency understands that no additions will be made to the list on Thursday, despite speculation that Spanish and Greek islands and Malta could be added.

Paul Charles, chief executive of travel consultancy The PC Agency, said this is a “terrible decision”.

He told PA: “They are basically putting at risk tens of thousands of jobs across aviation and the travel sector, and not showing any signs of helping the sector to recover.

“They seem to want to continue to create an atmosphere of fear among travellers, which is totally at odds with other countries.

“There are several countries which meet the criteria to be on the green list so this is clearly a politically charged decision rather than one based on data.”

Robert Boyle, former director of strategy at British Airways’ parent company IAG, said: “In theory, we know what is being measured and the data sources being used, as the Government has published that.

“What we don’t know is what the thresholds are and how they get from the data to the decisions.

“I think the truth is they follow the opinion polls.”

All changes to the lists will come into effect at 4am on Tuesday June 8.

The Government has previously said assessments of travel lists are based on a range of factors, including the proportion of a population that has been vaccinated, rates of infection, emerging new variants, and access to reliable scientific data and genomic sequencing.

People returning to the UK from red-list locations must stay in a quarantine hotel at a cost of £1,750 for solo travellers.