Government guidance on travel insurance has been reviewed and updated post Brexit.
If you travel internationally you should buy appropriate travel insurance before you go. If you already have a travel insurance policy, check what cover it provides for coronavirus-related events, including medical treatment and travel disruption, and any planned activities such as adventure sports. If you are choosing a new policy, make sure you check how it covers these issues.
If you do not have appropriate insurance before you travel, you could be liable for emergency expenses, including medical treatment, which may cost thousands of pounds.
See: Foreign travel insurance – GOV.UK (www.gov.uk)