The Covid testing rules for entering the UK have been changed - affecting anyone planning a trip abroad.
Because of worries about the Omicron variant, all travellers coming to the UK now need to take a test before they set off - and another when they arrive.
Before departure: All travellers to the UK aged 12 and over have to show proof of a negative test, even if they are fully vaccinated.
This can be a PCR or a lateral flow test, and must be taken in the two days before departure for the UK.
You'll need to find a private test provider for this - free NHS lateral flow kits are not allowed.
The test can be taken either in the country where you start your journey, or in another country en route to the UK (for instance if you're travelling overland).
If you test positive, you should follow local rules in place in the country you're in, and do not travel to the UK.
After arriving in the UK, you have two days to take another test - which must be a PCR.
This must be booked before you travel, and bought privately from a government-approved list of providers.
While you are waiting for a result, you must self-isolate - whether or not you have been vaccinated. You can stop self-isolating if your test is negative.
Everyone aged five and over (11 and over in Scotland) must take these tests.
In addition, all travellers coming to the UK must fill in and submit an online passenger locator form no more than 48 hours before arriving - even if they are just passing through the UK.
The testing rules do not apply to travellers from Ireland, the Channel Islands or the Isle of Man (unless they have been in another country in the 10 days before departure for the UK).
You will only have to quarantine if you have come from a country on the UK's travel red list.
Currently, this includes Angola, Botswana, Eswatini, Lesotho, Malawi, Mozambique, Namibia, Nigeria, South Africa, Zambia and Zimbabwe.
These countries have been targeted because the Omicron variant was first identified in southern Africa.
The only people allowed to enter the UK from red list countries are UK or Irish nationals, or UK residents.
They have to pay for and self-isolate in a pre-booked government-approved hotel for 10 days.
Test results can be in the form of a printed document, or an email or text on your phone. They must be in English, French or Spanish.
European Union residents can use the EU Digital Covid Certificate to show their vaccination status or test results.
The current UK rules say that if you aren't fully vaccinated - and you're over 18 - you need to:
Test to Release will remain an option for unvaccinated passengers to England who want to shorten their quarantine.
These are the rules for getting into the UK - you'll also need to check the UK Foreign Office website for entry requirements of any other countries you visit. These can change quickly.
Covid passes issued in the UK can be used throughout the EU to show proof of vaccination - either digitally, or as a printed download (as long as it is dated later than 1 November 2021).