Under the plans, the majority of fully vaccinated travellers arriving from non-red list countries will no longer have to take a test before setting off for the UK.
Fully vaccinated residents – and unvaccinated under 18s – from more than 50 countries and territories can now enter the UK without a pre-departure lateral flow test, take a day-eight post-arrival PCR test costing around £65, or self-isolate at home.
Arrivals into England will still need to take a PCR test on their second-day in the country.
It comes amid reports the number of countries on the red list will be slashed to nine from 54 later in the week, with destinations such as Brazil, Mexico and South Africa expected to be opened up to quarantine-free travel.
People arriving from a red tier destination will still be required to spend 11 nights at a quarantine hotel costing £2,285 for solo travellers.
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Transport Secretary Grant Shapps said the latest move is part of move to "accelerate towards a future where travel continues to reopen safely and remains open for good, and today’s rule changes are good news for families, businesses and the travel sector.
“Our priority remains to protect public health but, with more than eight in 10 people now fully vaccinated, we are able to take these steps to lower the cost of testing and help the sector to continue in its recovery.”
The easing of the quarantine and testing regulations – announced last month – has been welcomed by the travel sector.
Airlines and tour operators have been badly impacted during the Covid-19 pandemic, with many accusing the government of being too slow to relax and simplify the rules for international travel.
Tim Alderslade, chief executive of Airlines UK, a trade body representing UK carriers, said: “We’ve seen a good response to the announcement in terms of bookings and given current trends we would hope to see more countries come off the red list and further mutual recognition of vaccine status.
“There is still much to do though. This is not job done, and ministers need to keep in mind that we remain an outlier on arrivals testing for vaccinated passengers.
“In the short-term the removal of PCR testing by the October half-term week is critical, and we look forward to clarity on the start date for this as soon as possible.”
No date has been set for when eligible fully vaccinated travellers arriving in England can use a cheaper lateral flow test rather than a PCR version for the day-two post-arrival test.
The Department for Transport said the government “aims to have it in place for when people return from half-term breaks”.