High-tech eye scanners designed to reduce the time taken for passengers to enter the UK have been scrapped at two airports and closed to anyone who has not already registered, the UK Border Agency (UKBA) said.

The future of the Iris Recognition Immigration System (Iris), which has been criticised for adding to delays rather than cutting queues, is being reviewed and the system has already been scrapped at both Manchester and Birmingham airports.

It has also been closed to all new applicants since last year, but will remain open for registered passengers travelling through terminals, 1, 3, 4 and 5 at Heathrow Airport and Gatwick North until after the Olympic and Paralympic Games this summer, the UKBA said.

A UKBA spokesman said: "With electronic passport gates now operating at 15 of the country's busiest airport terminals and available to millions of biometric passport holders, Iris is just one of the options for travellers to securely enter the UK.

"We are currently reviewing the long-term future of Iris."

On its website, the UK Border Agency (UKBA) added: "Iris is no longer available at Birmingham and Manchester airports."

It went on: "Registration for Iris is no longer available.

"All of our enrolment rooms at Heathrow, Gatwick, Birmingham and Manchester airports are closed until further notice."

The Iris scheme was criticised five years ago when an official report on trials of the technology showed it had failed half of its assessments.