As Omicron cases rise across the world, the government has focused on tightening restrictions at the border for those wishing to travel overseas in the coming weeks.
Currently, passengers travelling to the UK must get a negative result from a pre-departure Covid-19 test (PCR or lateral flow) before their arrival. This is as well as taking a PCR test when you get back into the UK too.
Amid these recent changes, ITV News outlines what you need to know if you're planning travel abroad.
What do I need to do if I'm travelling to the UK?
From 4am on Tuesday, fully vaccinated passengers must show a negative PCR or lateral flow test result taken in the 48 hours before your arrival in the UK.
You'll also need to complete a passenger locator form, to be done 48 hours before you arrive back in the UK.
You must also take a PCR test on or before your second day back in the country and self-isolate until you get your result.
If negative, you can then return to life as normal but if positive you'll then need to continue to self-isolate, in line with NHS guidance, for a full ten days.
If unvaccinated, travellers must take a Covid test 48 hours before arriving in the UK and complete their passenger locator form. They'll then need to isolate for a full ten days once they've arrived within the UK and take two more private PCR tests, on days two and eight.
Where can I get the Covid test from?
You can purchase a test in the country where you start your journey or in another country on the way to the UK.
The test must meet performance standards of ≥97% specificity or ≥80% sensitivity at viral loads above 100,000 copies/ml. These include PCR and lateral flow tests.
You will not be permitted to use NHS tests for pre-departure testing.
For the PCR test to take by day two back in the UK, you'll also need to purchase one privately.
What about children?
If you're travelling with young children, aged four and under, they will not need to take any Covid travel tests.
From 7 December at 4am, children aged 12 to 17 must take a PCR or lateral flow test within the 2 days before travel to the UK - the same as adults.
Children aged five to 17 have to follow the testing and quarantine rules for people who qualify as fully vaccinated on arrival in England - so that means quarantine on arrival and take a PCR test on or before day two.
Do I need to take a test if I'm flying from the Republic of Ireland or Northern Ireland?
No. You also don't need one if you began your journey in the following places:
the Isle of Man
Jersey or Guernsey
St Helena or Ascension
But if you've stopped at one of these places having been elsewhere overseas in the ten days prior, you will still need to do a pre-arrival test and a day two PCR.
You also do not need to take a pre-departure PCR test if you began your journey to England from Ethiopia - it's a temporary measure due to the current security situation in the country.
What about the red list?
Immediately after scientists in South Africa altered the world to Omicron, 11 southern African countries were put on the red list, meaning people need to quarantine in a hotel upon arrival in the UK.
But with Omicron cases now so prevalent in the UK, the red list for international travel has been scrapped in England and Wales. It is unclear whether Scotland and Northern Ireland will follow.
The red list, which was reintroduced in late-November, forces 11 nights of hotel quarantine upon everyone who arrives from those countries at a cost of £2,285 for solo travellers, regardless of their vaccination status.
Other border measures, brought in as a response to the Omicron variant, will remain in place.
As a British passport holder, are there any restrictions on where I can travel?
From midnight on Friday, people arriving from Britain will be required to show a negative Covid test that is less than 24 hours old, to test again upon arrival and self-isolate for seven days, although that can be reduced to 48 hours if the second test is negative.
Tourism and business trips will be limited and French travellers are being dissuaded from visiting the U