Just eight countries may be declared safe for summer holidays this year, according to a new report.
Ireland, Iceland, the USA and Malta could be put on the green list for foreign travel, along with Israel, Australia, New Zealand and Gibraltar.
Of those - both New Zealand and Australia are currently closed for tourists, meaning there could be just six safe holiday destinations, reports The Mirror.
All other countries would end up on an amber or red list. Red meaning no non-essential travel, and amber meaning restrictions such as quarantine.
The lists are set by each nation in the UK - with different rules in England, Wales, Scotland and Northern Ireland - but in the past have been broadly in line.
A report by Robert Boyle, former strategy chief at BA, and circulated in the travel industry, said that most of Europe will be classified as "amber" or "red" - meaning quarantine will be required, according to The Telegraph.
The report ranks 52 countries based on vaccination rates, infection levels, variants and capacity for genome sequencing - the four criteria used by the UK government.
People arriving from countries listed as "red" would be required to quarantine at a hotel at a cost of £1,750 when they return to England.
France, the Netherlands, Turkey, Croatia, Sweden, Belgium and Luxembourg should be "red" under the criteria, researchers found, but this is unlikely to happen for political reasons, the report said.
Countries classified as "amber" will require people to quarantine at home for 10 days after arrival.
High Covid rates in Spain, Greece, Italy and Cyprus mean they are likely to be "amber" - but it is possible islands will be given their own rating.
The report said: “Last year, the Spanish and Greek islands were given a lower-risk rating than the mainland, and that could happen again this year."
Just five countries have vaccinated more than five per cent of their population - the US, Israel, Gibraltar, the UAE and Malta - while only seven have less than 50 cases per million people.
These are China, Hong Kong, Australia, New Zealand, Israel, Iceland and Gibraltar.
Variant rates are worst in Turkey, Luxembourg, Finland, Belgium, France, Holland and South Africa, The Telegraph reports.
