- Coronavirus pandemic
image copyrightPA Mediaimage captionAfter a brief stint on the green list, Portugal is now classed as amber meaning arrivals from there must self-isolate
Details about how and when fully vaccinated travellers can return from certain countries without having to quarantine are to be set out later.
Transport Secretary Grant Shapps will make a statement to MPs this morning.
Currently, those arriving in the UK have to follow strict rules regardless of their vaccine status, and anyone returning from countries on the amber or red list must isolate for 10 days.
Travel bosses have called for the rules to be eased as soon as possible.
The UK's traffic light system for international travel is still in force. Fewer than 30 destinations are on the green list – meaning travellers do not have to self-isolate when they get back to the UK but they do have to pay for Covid tests.
More than 50 countries are on the strictest red list, which requires arrivals to pay to self-isolate in a hotel for 10 days.
But most places – including several holiday hotspots such as mainland Spain, Greece and the USA – are on the amber list. People returning from these countries must quarantine for 10 days and pay for tests.
- What are the green, amber and red rules?
- How can I prove I've had both my Covid jabs?
- The rules for holiday spots like Portugal, Malta and Spain
The government has already said it was planning to scrap the need to quarantine for those who are double-jabbed and returning from amber countries.
But it has not set out how it would work, when it would happen, and whether unvaccinated children would also be able to avoid quarantine if their parents are fully vaccinated.
Mr Shapps will update the House of Commons at 11:30 BST.
The UK government's traffic light system applies to England, with Scotland, Wales and Northern Ireland able to make their own rules.
However, the rules are broadly the same and previous changes to the lists have been adopted by all four nations.
Not just about holidays: 'My daughter couldn't come back for dad's funeral'image copyrightMelanie Matheisimage captionMelanie's husband was diagnosed with cancer last summer
Melanie Matheis lives in California. Her daughter Allana left to go to drama school in London in September, and a few months later Melanie's husband died after being diagnosed with cancer.
Allana couldn't come back for her father's funeral or for Christmas because of the UK's travel restrictions.
"She wouldn't have been able to go back to school when she went back to London because of the quarantine," Melanie tells the BBC, "so she made the difficult decision to stay there."
She adds: "It was difficult for myself as well being alone."
Melanie is double-jabbed and was hoping to visit her daughter in London this month, but has put it back by a few weeks once it became clear the rules were not changing. The US is on the UK's amber list, meaning Melanie would have to quarantine somewhere when she arrives.
Without a home here, she would have to pay for a hotel room and tests which she can't afford. "It would be double the expense and it's just not really possible," she says. "It would make it very difficult."
The travel industry is eager to have the rules relaxed.
Daniel Pearce, the boss of monthly magazine for the travel industry, Travel Trade Gazette, said the industry had been "crying out" for quarantine exemptions.
He said he hoped changes would coincide with the wider easing of lockdown rules in England on 19 July.
"Any change as early as this would enable some form of summer season to take place during the children's school holidays," he said.
Removing quarantine rules for some travellers would be a huge boost for the industry, but there are still plenty of questions that need to be answered.
Will unvaccinated under-18s be allowed to travel without quarantining? How will the new system work?
Will it be open to every country or only to those jabbed in the UK? If it is UK only to start, when will it open up more widely?
And crucially, when will it start? The travel industry is desperately hoping it will be from 19 July, but if it doesn't start until August, they will miss out on much of the family holiday market.
On top of this, it's always worth remembering that these policies are just about what the UK requires of people arriving here.
For international travel to start to flow again, other countries need to let us in too.
However, other groups are concerned about the plan to open up society further.
In a letter to medical journal The Lancet, more than 120 scientists and doctors have called on the UK government to rethink its plan to end restrictions in England on 19 July, calling it "dangerous and premature", saying millions more people will became infected if it goes ahead.
The government should wait until everyone, including adolescents, have been offered the vaccine before opening up, they say.
More than 32,000 new coronavirus cases were announced on Wednesday, as well as 33 more deaths.
Nearly two-thirds of the adult population in the UK have received two jabs, and 86% have had a first dose.
The government has said that public health remains its priority and it is taking a cautious approach to the resumption of international travel.
The UK government reviews which countries are on which list every three weeks, and the last update was three weeks ago on 24 June, meaning the next update is due in a week.
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