Coronavirus: What are the UK travel quarantine rules?

However, travellers from Portugal to England have been told they will not face quarantine, despite fears that restrictions might be reintroduced.

Almost everyone entering the UK - including British nationals - must fill in a ''passenger locator'' form, regardless of whether or not they need to quarantine.

The form asks travellers to provide their contact details and UK address.

If someone who is required to self-isolate does not provide an address, the government will arrange accommodation at the traveller's expense.

For 14 days, starting from the day after arrival, people who are quarantining should not:

People returning from overseas will not be automatically eligible for statutory sick pay during this period, unless they meet the required conditions - for example, displaying coronavirus symptoms.

The government has warned travellers that breaking quarantine rules is a criminal offence, and that they face a fine and potentially a criminal record.

Those not self-isolating when they are supposed to can be fined £1,000 in England, Wales and Northern Ireland, or £480 in Scotland. There are fines up to £5,000 for persistent offenders.

They can be fined up to £3,200 in England if they do not provide accurate contact details, or £1,920 in Wales.

There is also a fine of £100 for not filling in the passenger locator form.

One in five eligible passengers will be called or texted to check they are following the rules.

Travellers from more than 50 countries deemed ''low risk'' do not have to quarantine, although some of these countries impose restrictions on travellers entering from the UK.

The government publishes a list of these ''travel corridor'' countries.

Anyone arriving from the Common Travel Area (CTA) - the Republic of Ireland, the Channel Islands, or the Isle of Man - does not have to enter quarantine if they have been in the CTA for at least 14 days.

Health measures including quarantine rules are set by each UK nation separately - although Wales has largely adopted the same exemptions as England.

Since 10 July, Scotland's quarantine measures have also been eased, as have Northern Ireland's. However, Scotland's travel corridors have differed slightly from the rest of the UK at times.

Anyone entering the UK from a country not on the travel corridor list - such as Sweden, Russia and the US - is required to quarantine.

This list now includes several countries previously exempt:

Travellers from Greece to Scotland are being asked to self-isolate for 14 days.

Wales has asked people arriving from Portugal and six Greek islands who arrive after 04:00 BST on Friday to quarantine.

Travellers from Greece to England and Northern Ireland are unaffected.

You don't need to self-isolate if you drive through a non-exempt country, as long as you don't stop in the country to get out of the car and no-one else gets in.

If you are on public transport, you are exempt from quarantine if no new passengers get on while in the non-exempt country and no passenger mixes with people outside or enters a public space at a stop.

There are a number of people who are exempt, regardless of where they are flying from, including:

Travellers could find they also have to enter quarantine when they arrive in another country, even if they do not have to quarantine in the UK on their return. Some countries have introduced screening measures like temperature checks and entry restrictions. For example:

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