The first passengers have been arriving in the UK after rules changed to allow people fully vaccinated in the US and EU to avoid quarantine.
The change, which came in at 04:00 BST, affects those arriving from countries on the UK’s amber list – except France.
The UK government said the change would help to reunite family and friends whose loved ones live abroad.
Airline bosses have welcomed the move but are calling for more countries to be added to the UK’s green travel list.
One man who was among the first arrivals from the US said it was “amazing” to be able to finally come back from Washington DC to see friends and family without having to isolate.
“It gives us an opportunity to spend time with family – people we haven’t seen for quite some time,” he said.
“As soon as we got off the plane we got so excited, even the little ones were shouting ‘London, London’. It’s just absolutely marvellous to be back.”
Travellers will still need to take either a lateral flow or PCR test pre-departure, and a PCR test on the second day after they arrive. Under-18s will be exempt from isolation, and some will not have to test, depending on their age.
Since 19 July, people who have been double-jabbed in the UK have not had to isolate when arriving from amber list countries, but all other travellers vaccinated elsewhere are required to quarantine for 10 days.
Tougher rules also remain in place for France, with travellers still required to quarantine even if they have been double jabbed.
Transport Secretary Grant Shapps has said this will be reviewed at the end of the week at the next review of the travel lists.
What are the traffic light system rules?
- Green country: When returning from a country on the green list you must take a Covid-19 test before departure and have proof of a negative result. You also need to book a test for day two after your return
- Amber country: A Covid test is needed three days before returning, and a PCR test two days after arriving. People who are not fully vaccinated in the approved countries need to self-isolate for 10 days, although this can be shortened for people in England by using the Test to Release scheme – paying for a test on day five
- Red country: Regardless of your vaccination status you must take a test before departure and, on arrival, self-isolate for 10 days in a government-approved quarantine hotel
Others to welcome the change included nurse Elaine Burt, 55, who was waiting at Glasgow Airport for her sister and nephews to arrive from Boston in the US – their first meeting in 20 months.
“We never thought it was going to happen with all of the different restrictions but we left it to the last minute to see what was possible. I can’t wait,” she said.
Student Ben Hamilton, 19, from Texas, said it was a “relief” not to have to isolate after he landed back in Scotland.
The Glasgow University veterinary medicine student said: “It’s the first time I’ve got back and not had to quarantine.”
Heathrow Airport chief executive John Holland-Kaye said the UK’s current travel rules were “still quite complicated” and needed to be simplified to make it easier for people to travel, as well as reducing some of the extra costs.
He told Radio 4’s Today programme: “We need to get rid of the requirement for everyone to have a PCR test and replace it with a simpler, cheaper lateral flow test as a first line of defence.”
The leaders of UK airlines described Monday’s easing of the rules as a “positive step” but said they were concerned that the UK aviation sector was not on the path to recovery “due to the continued restrictions that are being imposed on international travel”.
In a letter to Mr Shapps, they wrote that green status should “increasingly become a default” for countries, citing falling case numbers and the proportion of the UK population now vaccinated.
As part of the changes, international cruise ships will be able to depart from England from Monday – after a 16-month pause.
International cruises have been allowed from Northern Ireland since Saturday.