Denmark are among the seven countries moving to the green list in the recent Covid border changes.
Thailand and Montenegro are added to the UK government's red flag - meaning they are considered the most dangerous places.
Finland, the Azores, Switzerland, Liechtenstein and Lithuania are also on the green list.
Travelers from green-listed countries do not have to part with their return from the UK - even if they already have two doses of coronavirus vaccine. They still have to be tested before returning to the UK however, and book a second day test after their return, and then fill out a local passenger form.
But while Canada is on the green list, it currently has a policy for British citizens to enter the country.
Only UK or Irish citizens, or UK citizens, are allowed to enter the UK when they list red countries. After that they have to pay to isolate themselves from a government-approved hotel.
The Department of Transport said the change was made to the red list to indicate "an increase in the number of cases in these countries and the greater risk from these countries to the public health of the UK".
The checklist is currently updated every three weeks. Most countries are on the amber list - fully vaccinated adults do not have to be separated from their return from these areas, but should have a pre-return test and two days of return. Those who do not have both vaccines should be separated from home for ten days, as well as a Covid test.
The UK airline, which represents carriers registered in the UK, said "a small number of green spaces" makes international travel "more expensive, more difficult and less secure compared to other countries".
The spokesman said: "Too many families have to look to their shoulders for a change in the rules and pay for the test, with no sign from the government that this will change.
"As has happened throughout Europe, it is time for a balanced program to reduce the number of people who are completely vaccinated and in areas where Covid's risk is low, and severe measures are targeted at high-risk countries."
Sean Doyle, Chairman of British Airways and CEO, responded to the tourism revolution by saying "economic recovery in the UK is still a long way off from our courageous European neighbors". He added: "We must also urgently eliminate the uncertainty created by the ongoing threat of evolution from robots in countries.
"Our green list is much smaller than that of the US and the EU, although there is little new shipping in the UK."
Charlie Cornish, chief executive of the Manchester Airports Group operating at Manchester, London Stansted and East Midlands airports, said changes in the traffic light system would make "little difference" in restoring the tourism industry and urged the government to "fix things" it.
He said unless the government eliminates the need for fully vaccinated people to take the tests, "it will continue to waste the benefit that our world-class vaccination program should have delivered".
Shadim Transport Secretary Jim McMahon warned "any border restrictions are dangerous, especially various ones that could impede the progress we have made in vaccines".
Scotland Transport Secretary Michael Matheson said the changes were "welcome to Scots and loved ones in Canada but also show that international travel remains a challenge".