- Coronavirus pandemic
image copyrightPA Mediaimage captionThe last review, which was three weeks ago, saw Portugal removed from the green list
The UK's rules on foreign travel are set to be reviewed later, after industry bosses united in a desperate plea for the green list to be widened.
Transport Secretary Grant Shapps will face MPs later this morning, with an update on the traffic light system expected in the afternoon.
Travel bosses are calling for an exemption to quarantine for fully-vaccinated people from amber countries.
Mr Shapps has said ministers "need to look at what the science says".
But the prospect of European holidays could face another hurdle, after German Chancellor Angela Merkel suggested all EU countries should make British travellers quarantine on arrival to slow the spread of the Delta variant.
She told Germany's parliament: "In our country, if you come from Great Britain, you have to go into quarantine – and that's not the case in every European country, and that's what I would like to see."
- What are the green, amber and red rules?
- How can I prove I've had both my Covid jabs?
- What's happening with foreign travel?
Currently, just 11 destinations are on the green list – including Gibraltar, Israel and Australia. Travellers do not need to quarantine when they get back from these countries, but they do have to pay for tests.
Most holiday hotspots are on the amber list, meaning arrivals must self-isolate for 10 days when they return as well as pay for tests – and the travel sector says this has been devastating for bookings. Countries on the red list are considered the highest risk, and travel from those countries is more strictly limited.
The UK government reviews which countries are on which list every three weeks, and the last update – when Portugal was stripped from the green list – was three weeks ago on 3 June.
As well as today's review, the government has also said there will be a "checkpoint" review of the rules for each category on Monday 28 June. That could be when ministers decide whether to relax quarantine for fully-vaccinated travellers.
On Wednesday, Mr Shapps told the BBC: "If you've been double vaccinated then of course we need to look at what the science says. We've said that Monday is the point to review that data, so we are coming up to having a look at it.
"We're looking at it in the next few days and I'll have more to say."
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.
The travel industry is nervous.
The school summer holidays, a crucial time for the sector to make much of its income, are looming and most holiday destinations are on the amber list, meaning arrivals from there to the UK have to quarantine at home and pay for at least three Covid tests.
Few are feeling optimistic that today's expected announcement will see many destinations added to the green list.
But the industry is more hopeful that there could be news about removing the quarantine requirement for fully vaccinated passengers from amber list countries – though there is no guarantee whether or when this could be introduced.
Ministers have always said that their international travel policy will be guided by protecting public health.
Earlier this week, Health Secretary Matt Hancock said ministers were "working on" plans for fully-vaccinated people to be exempt from quarantine if they returned from amber-list countries.
More than 60% of UK adults have now been fully vaccinated, while 82.5% have had their first jab.
The latest daily Covid figures for the UK also showed a further 16,135 confirmed cases and 19 further deaths.
Hospital admission data is not updated as frequently as cases, deaths and vaccinations, but the most recent data – from 21 June – showed there were 1,508 people being treated for Covid in hospital.
On Wednesday, workers in the travel industry including cabin crew, pilots, travel agents and airport staff held a series of protests against the rules.
They called on the government to offer the industry more financial support and increase the number of countries on the UK's green list.
And industry body Abta, representing travel agents and tour operators, estimated 195,000 travel jobs have been lost during the pandemic or are at risk.
media captionHow one airline is keeping its aircraft and staff ready to fly
The government said its international travel policy was guided by "one overwhelming priority – protecting public health".
It said a range of factors are considered when making decisions about countries – including how capable a country is at genomic sequencing, the risk of transmission and the risk from any variants of concern.
The government added it was keeping all possible travel measures under review, and that economic support for the sector included the furlough scheme.
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