Transport secretary Grant Shapps confirmed that from Tuesday, Portugal will be taken off the United Kingdom foreign travel green list, which now allows travellers from those countries into England without having to self-isolate on arrival, while no new countries will be added.
There has been a furious reaction to an announcement made by the Northern Ireland Executive that will see Portugal taken off of the green list and put onto the amber list next week.
Arrivals in the United Kingdom from green list destinations are not required to quarantine, but must take a PCR Covid test on day two of their return.
Reports also note "a strong expectation" more countries will be added to the red list today.
That means people arriving in the United Kingdom from those nations will now be required to stay in a quarantine hotel for 11 nights, at the cost of £1,750 for solo travellers.
The rise has been driven by the Delta variant, which originated in India.
It comes as United Kingdom prime minister Boris Johnson previously warned that the government would not hesitate to drop countries from the green list.
Managing Director for TUI UK Andrew Flintham said: "This latest announcement is another step back for our industry".
"I want you to know we will have no hesitation in moving countries from the green list to the amber list to the red list, if we have to do so. They have failed on this promise".
Travel Consultancy CEO Paul Charles told us: "This move by the government defies logic, because there are some countries that meet the government's criteria to go on the green list. The priority is to continue the vaccination rollout, to protect the people of this country". Other European countries that were thought to make the green list were Finland and Poland.
Summer travel hotspots including Malta, and Spanish and Greek islands, had hoped to be awarded green status previously given to Portugal.
Most popular European destinations stayed in the amber category, which means arrivals must self-isolate for 10 days upon entry into the United Kingdom, plus take PCR tests on days two and eight.
"Absolutely scandalous how the government is treating us", said one Northern Ireland man. "We've got to follow the data".
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.