When will the green list be announced and who will be on it?

International leisure travel may resume from the UK on 17 May, the government has said.

But strict rules on returning to the UK will be enforced – based on a “traffic light” system that assigns red, amber or green to every overseas country. The main concern is that variants of concern could be imported and ultimately undermine the UK’s vaccination programme.

The Independent has canvassed opinions in the travel industry and researched the data on which the government will decide. These are the key questions on what we know – and don’t know – so far.

What are the current rules?

At present holidays and family visits abroad are illegal, under legislation to reduce number of people coming into the UK. Around 20,000 travellers are arriving in the UK from abroad each day, not counting hauliers.

A de facto traffic light system already exists for arrivals to the UK.

The only foreign country with “green” status is Ireland. Neither tests nor quarantine apply for arrivals to the UK from the Republic.

From all other nations, a negative Covid test is required before departure to the UK.

At the high-risk end of the traffic light spectrum, countries perceived as presenting special danger are on the UK’s red list. At present 39 nations are listed, mainly in southern and eastern Africa and in South America – but also including the UAE, Qatar, Pakistan, Bangladesh and the Philippines.

Arrivals from red countries must pre-pay for 11 nights in hotel quarantine – at a cost starting at £1,750 – plus two post-arrival PCR tests.

Every other nation is rated at “amber” – which requires 10 days self-isolation at home plus two PCR tests. Paying for a third post-arrival test on day five can trigger early release.

The amber list applies only for arrivals to England. Scotland has tougher rules on inbound travellers, regarding all nations (apart from Ireland) as red list. Wales and Northern Ireland do not currently have arrivals from overseas countries.

Read more: Which countries are on the red list?

What will change?

According to the latest Global Travel Taskforce report, subtitled “The Safe Return of International Travel,” a list of green nations regarded as low risk will be compiled and published before the restart of trips abroad.

Arrivals from green countries need not quarantine but must take a PCR test within two days of arrival. The cost is likely to be around £60.

Restrictions on red and amber nations are likely to stay as they are.

Countries may be moved from one category to another at any time. But the government says it will also introduce a “Green Watchlist” that will “identify countries most at risk of moving from green to amber”. This has become known as “flashing green”.

The idea is to avoid the chaos last July when, for example, Spain was placed on the quarantine list at just a few hours’ notice.

Instead the aim will be to give at least a week’s warning, so that most holidaymakers can finish their trips as normal – and anyone booked to travel to a “flashing green” nation can consider whether or not to go.

The government stresses that there is no guarantee of a week’s notice and that decisions on moving countries from green to amber or red will be taken on the basis of data.

In addition, each destination abroad will come up with its own stipulations for accepting or rejecting overseas visitors. Those decisions are, of course, beyond the scope of the UK government.

When do we find out which nation is on which list?

“As soon as we possibly can,” the prime minister said at a Downing Street briefing on 20 April – but Boris Johnson added that it would not be before early May.

The Global Travel Taskforce report emphasises that no decision about whether to open up leisure trips abroad will be taken before then: “We cannot yet confirm resumption of international travel from 17 May. We will provide further details by early May.”

The aviation minister, Robert Courts, told the Transport Select Committee: “We need to be in a position whereby when we make those decisions it is on the data that exists at that time. We are still some distance away from that date at the moment.

“I anticipate that in the early part of May we will be able to give some more detail into which category each country will fall.”

The Independent has sought more clarification on when exactly travellers and the travel industry will learn the details, but the Department for Transport (DfT) has been unable to be more specific.

“Early May” covers every date between 1 and 15 May. The assumption in the travel industry is that the announcement will not be made over the weekend of 1 and 2 May, and that it is likely to happen in the working week beginning on Monday 3 May.

But some people with political connections have told The Independent that the government may give only one week’s notice, pushing the announcement back to Monday10 May. The thinking is that the closer the announcement is to the restart, the more certain the data and the lower the chance that the lists will have to be hurriedly amended.

What is the response of the travel industry?

Simon McNamara of the International Air Transport Association (Iata), said: “The report talks about early May; it does not even give a hard date for when the classification will be set.”

Peter Liney, chief executive of Great Rail Journeys, confirmed this view, telling The Independent: “Say they say on 3 May all of Europe is going to be green. We wouldn’t try to run our May programme.

“You can’t run the business on speculation in the media about what countries will be in green.”

Huw Merriman, chair of the Transport Select Committee – and, like Robert Courts, a Tory MP – said: “It is going to be incredibly difficult for anyone to book a holiday for summer if they do not know what the rules of the road are going to be.”

What are the government’s criteria for judging who goes on which list?

The status of a country’s vaccination programme, infection rates relative to the amount of testing, the prevalence of variants of concern and access to genomic sequencing (enabling variants of concern to be identified).

To be on the green list, a nation will need to have: