London mayor Sadiq Khan warned Saturday that Eurostar passengers going from Britain to the continent face "chaos" once a new computerised border scheme proposed by the European Union takes effect.
All visitors entering the EU with visas or visa waivers will have to go through the automated EU Entry/Exit System, which has been long delayed and now scheduled due to start in October.
Almost 19 million people used the Eurostar -- which connects Britain with Belgium, France, Germany and the Netherlands -- last year as traveller numbers returned to their pre-pandemic levels.
The system will record a non-EU national's details and biometric data along with their date of entry and exit, keeping track of overstays and refused entries.
"As it stands these new post-Brexit checks will cause chaos at St Pancras (the London station serving Eurostar passengers), with cuts to services and potentially huge queues facing passengers at peak times," said Khan.
Britain formally left the EU in early 2020 following the 2016 Brexit referendum, with its citizens losing the right to freedom of movement in the bloc.
The automated system will replace the stamping of passports for Britons travelling to France.
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