The government will categorise countries and reveal their status under a new traffic light system designed to govern the resumption of international travel "by early May".
Destinations will be sorted into green, amber and red categories based on four key criteria: the percentage of their population vaccinated against Covid-19; their rate of Covid infection; the prevalence of new Covid-19 variants of concern; and their access to reliable scientific data and genomic sequencing capabilities.
Additionally, a new "green watchlist" will highlight countries at greatest risk of being relegated from green status to amber, allowing travellers to plan their journeys with greater confidence.
The system is detailed in the long-awaited report from the government’s Global Travel Taskforce, which was tasked with demonstrating how international travel could resume from 17 May "in an accessible and affordable way".
Arrivals from countries categorised green will need to take a pre-departure test, as well as a PCR test on or before the second day of their arrival back into the UK. They will not need to quarantine upon their return, unless the test positive, or take any additional tests.
Amber arrivals will need to take a pre-departure test, quarantine at home for 10 days upon their return, and take PCR tests on day two and day eight of their quarantine. They can end their quarantine early by using the government’s Test to Release scheme.
Arrivals from countries in the red category must complete 10 days’ quarantine in a government-appointed hotel quarantine facility. They must also take pre-departure test, and PCR tests on day two and eight of their self-isolation.
On the new green watchlist, the taskforce says: "To give passengers more certainty when travelling, a ‘green watchlist’ will be introduced to help identify countries most at risk of moving from green to amber. The watchlist will provide greater assurance for those who wish to travel abroad.
"While the watchlist will warn travellers of potential changes in advance, the government will not hesitate to act immediately should the data show that countries risk ratings have changed.
"Government will set out an initial assessment of which countries will fall into each category, by early May, ahead of reopening international travel."