People arriving in the UK now have to take two coronavirus tests while quarantining, and some must pay to self-isolate at a hotel.
It's one of a number of rules aimed at stopping the spread of new, potentially more resistant Covid strains from other countries.
Rule-breakers face stricter penalties, including a prison sentence of up to 10 years for those who lie about having been in a banned "red list" country, such as Portugal.
What are the testing rules?
All incoming passengers must complete a passenger locator form in advance, including their departure country and UK address.
They also have to show proof of a negative Covid-19 test taken within 72 hours before travelling, to be allowed entry.
Travellers must then self-isolate for 10 days.
Arrivals must take a coronavirus test on days two and eight of quarantine, at a cost of £210. If they test positive, they must self-isolate for a further 10 days.
There is a £1,000 penalty for not taking the test, followed by a £2,000 fine for failing to take the second one, with quarantine automatically extended to 14 days.
The government says these measures will provide a "further level of protection", enabling authorities to track new cases more effectively.
A few workers are exempt from quarantine, including pilots and some seasonal agricultural workers.
Can I pay for a test to shorten quarantine?
Under the "test to release" scheme, travellers from countries not on the red list can take a test on day five of isolation.
People who test negative can stop isolating. Those who test positive must quarantine for 10 more days after the test.
Anyone using the scheme still has to take a further test on the eighth day.
Tests cost between £65 and £120.
Which countries are on the red list?
There are concerns existing vaccines may not work quite so well against some variants of coronavirus, including the South Africa and Brazil variants.
There are currently travel bans on 33 countries "where the risk of a new variant is greatest".
Travellers who have been in the following countries in the the 10 days before travelling are already banned from entry, unless they are UK residents or Irish nationals.
- Europe: Portugal (including Madeira and the Azores)
- Middle East: United Arab Emirates (UAE)
- Africa: Angola, Botswana, Burundi, Cape Verde, Democratic Republic of the Congo, Eswatini, Lesotho, Malawi, Mauritius, Mozambique, Namibia, Rwanda, Seychelles, South Africa, Tanzania, Zambia, Zimbabwe
- South America: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, French Guiana, Guyana, Panama, Paraguay, Peru, Suriname, Uruguay, Venezuela
The government has warned that other countries could be added with just a few hours' notice.
Hotel quarantine for 'red list' travellers
UK residents and Irish nationals arriving in England from red list countries will have to quarantine in hotels selected by the government.
People entering Scotland from any country by air have to isolate in hotels. Arrivals from countries in the Common Travel Area - the UK, Ireland, the Isle of Man, and the Channel Islands - are exempt.
These travellers can only enter the UK at five airports:
- London City
- Farnborough Airfield
In England, this will cost £1,750 per passenger travelling alone, to cover transport, tests, food and accommodation.
Every additional adult, or child over 12, costs £650, while children aged five to 12 cost £325.
Accommodation must be booked in advance through an online booking system.
Heathrow Airport has warned that "red list" travellers may face suspended flights and long queues at the border.
Arrivals will be escorted straight to their hotel and must stay in their rooms for 10 nights, with security guards accompanying them if they go outside. Households will be allowed to quarantine together, and some hotels may allow them to exercise.
Those who fail to quarantine in a designated hotel face fines of £5,000 to £10,000. Anyone who lies on their passenger locator form about having been in a country on the red list will face a prison sentence of up to 10 years.
Hauliers travelling from Portugal are exempt from hotel quarantine and do not have to present a negative test.
Who is allowed to travel outside the UK?
Lockdown rules mean people must only travel abroad for essential reasons. These are the same as the "reasonable excuses" for domestic travel, including:
- Work that cannot be done from home
- Medical appointments
- Educational reasons
People leaving England will soon have to make a declaration on why they need to travel, which will be checked by carriers prior to departure.
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