Boris Johnson has warned the Government will have 'no hesitation' in moving countries between the red, amber and green travel lists.
Asked whether there may be more countries added to the green list soon - where there are no requirements to quarantine on returning to the UK - the Prime Minister said they've got to be 'cautious' at the same time as allowing people to travel.
He said: "You’ve got to wait and see what the Joint Biosecurity Centre say and what the recommendations are about travel.
“We’re going to try … to allow people to travel, as I know that many people want to, but we’ve got to be cautious and we’ve got to continue to put countries on the red list, on the amber list, when that is necessary.
“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."
Mr Johnson added: "The priority is to continue the vaccine rollout, to protect the people of this country.”
It comes as speculation has mounted over which destinations will be added to the green list, paving way for hopeful holidaymakers to have more choice over where they can jetset away this summer.
According to the Evening Standard, Paul Charles, chief executive of the PC Agency travel consultancy, says he believes Majorca, Ibiza, Tenerife and Malta could all be moved from amber to green.
Mr Charles said analysis by his firm showed the Canary Islands, Finland, Jamaica, the Balearics, Barbados, Malta, Morocco and Grenada eight should be added to the green list.
However separate analysis by Robert Boyle, a former BA strategist, thinks only a small number of countries could be reclassified.
He said Austria, the Czech Republic, Germany, Italy and Luxembourg could also moved onto the green list.
Under the traffic light system, those heading to an amber country must quarantine at home when returning to the UK for ten days, and take a minimum of two post-arrival tests.
While tourists travelling to an area on the red list face the strictest rules. Only UK and Irish nationals, or UK residents, will be allowed to return from a red list country, and they must pay £1750 for a 10-day stay in a Government-approved quarantine facility.
Meanwhile, Boris Johnson has said there is still “nothing in the data at the moment that means we cannot go ahead with Step 4” of lifting coronavirus restrictions.
“But we’ve got to be so cautious,” he added, as he said infection rates were increasing.
It has not yet been confirmed when any changes will be announced - however the government previously said rules would be reviewed every three weeks.
This means changes from the next review could come into effect from Monday June 7.
