From today, all UK nationals and residents, who arrive in England after being in a high-risk Covid country, must now quarantine in a government-approved hotel for 10 days.
The "red list" of 33 countries includes Portugal, Dubai as well as a few countries in Africa and South America.
The new regime has been brought into place to stop the spread of new variants of Covid-19 entering the county.
Travellers will have to pre-book and pay £1,750 to spend 10 days quarantining in a government-approved hotel. This covers the hotel, food, transport and testing.
The booking portal is live for travellers to book their quarantine here.
Travellers must now get a negative test before flying (up to 72 hours before), pre-book hotel quarantine and then pass two Covid tests while in quarantine on days two and eight. Failure to pass either test will result in a longer quarantine.
All travellers arriving from other countries (non-high-risk destinations), must still quarantine at home for 10 days and complete two mandatory Covid-19 tests.
Fines of up to £10,000, as well as up to 10 years in jail, could be handed out to anyone who breaks quarantine or fails to fill in their passenger locator form accurately.
All travellers arriving into Scotland from abroad by air, from any country, will have to go into hotel quarantine.
Anyone heading to Wales or Northern Ireland from a high-risk country will be required to book and pay for quarantine in England, as neither destination has any direct international flights.