Travellers going to the US will need to have completed the new Electronic System for Travel Authorisation as of today.
The new online system is run by the US Department of Homeland Security as part of its Visa Waiver Programme and the authorisation, which it is recommended should be filled out 72 hours before departure, will replace the green slips travellers currently fill out once on their flights.
The registration allows for multiple entries and is valid for up to two years and has been introduced in order to ensure those wishing to visit the US have permission to do so before boarding their flights.
It is hoped the changes will help cut down on wasted journeys for people denied entry upon their arrival to the US.