From 25 February, non-visa nationals will be barred from entering the UK without and Electronic Travel Authorisation (ETA).

It is now mandatory for visitors to the UK to have obtained digital permission to travel. Airlines will prevent passengers from boarding if they don't have an ETA, eVisa or have other valid documentation.

The changes will apply to visitors of 85 nationalities, including nationals of the United States, Canada and France.

An ETA will cost £16, permit multiple journeys and last for two years unless the holder's passport expires.

British and Irish citizens, including dual citizens, are exempt from needing an ETA but will be required to present either a valid British passport or Certificate of Entitlement when travelling to the UK.

The enforcement of the ETA scheme is a step towards digitising the immigration system and lays the foundation for a contactless UK border in the future.

Minister for Migration and Citizenship, Mike Tapp said: "The ETA scheme is a vital part of our work to strengthen the UK’s border security, helping to deliver a more efficient and modern service that works for both visitors and the British public.

"I’d urge anyone wanting to travel to the UK to ensure they are travel ready and have the right permission, to make their journey much smoother."