The UK’s red travel list is expected to be slashed in a Government announcement on Thursday.
This would open up travel between the UK and dozens of long-haul destinations.
There are currently 54 countries on the red list, such as Mexico, Cuba, all of mainland South America, and southern and eastern Africa.
Anyone arriving in the UK from a location in the red tier must spend 11 nights in a quarantine hotel.
This costs £2,285 for solo travellers, making such trips unaffordable for many people.
A decision on which countries will be removed from England’s red list is expected to be made following a meeting of Government ministers on Thursday.
The devolved administrations in Scotland, Wales and Northern Ireland set their own travel rules but have recently mirrored announcements made in Westminster.
Paul Charles, chief executive of travel consultancy The PC Agency, predicted that only a handful of “less visited areas” such as Afghanistan, Haiti and Somalia will remain on the red list, with the “blanket measures on Africa and South America removed”.
He told the PA news agency this will be “a major step forward” as it means the Government will “finally move to a policy of individual risk”.
Travellers who are not fully vaccinated must self-isolate at home for 10 days when arriving from a country not on the red list, but those who have been jabbed are exempt.
The removal from the red list of Mexico, South Africa and Thailand would send “a confidence boost across the sector and across consumers”.
Mr Charles said it is “very hard to justify” why any countries are on the list “when there are no new variants of concern there”.
He continued: “That’s why Ireland have removed every country from their red list because they see no threat. So the UK should be following that example.”
The London-based World Travel and Tourism Council, which represents private firms, said the sector’s recovery will continue to be “sluggish” due to policies such as the UK’s red list.
The organisation predicted that travel and tourism’s contribution to global gross domestic product (GDP) is set to rise by less than a third in 2021.
Meanwhile, coronavirus data analyst Tim White believes “up to 18” countries could remain on the red list.
I've been away for far too long. But the day before the updated red list is announced I have managed to go through all the #coronavirus data.
I'm not going to say 9 countries which will be on the red list come tomorrow as I still think that's optimistic and it could be up to 18
— Tim White (@TWMCLtd) October 6, 2021
Writing on Twitter, he described reports that the list could be cut to just nine as “optimistic”.
Mexico “looks certain to be removed” but Thailand “may well stay red”, Mr White predicted.
The Government may use the travel update to confirm the date when fully vaccinated people arriving in England will be able to use a cheaper lateral flow test rather than a PCR version for their day-two test.
The Department for Transport said on Monday that this policy will be implemented “later in October”, adding that the Government “aims to have it in place for when people return from half-term breaks”.