A formal announcement is expected on Friday about which countries will be on the safe list when international travel starts again on May 17.
Speculation last week that the list could include holiday islands like Ibiza, Mallorca and the Canaries was wrong, officials said.
Under the traffic light system countries will be graded red, amber or green based on case numbers and vaccine rates.
Those returning from red countries will be required to complete hotel quarantine on their return.
Travellers returning from green countries will have to take a PCR test when they return to the UK but will not have to self-isolate.
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The UK could donate 120 million Covid vaccines to struggling countries
Professor Peter Openshaw said the UK could be donating about 120 million doses of vaccine to struggling countries.
Prof Openshaw, who is a member of the New and Emerging Respiratory Virus Threats Advisory Group (Nertag), told the Andrew Marr Show that it was best to work through the World Health Organisation (WHO) rather than giving it directly to…