ICAO Biometric Passport standards
The International Civil Aviation Organization (ICAO)—a UN agency responsbile, among other activities, for the standardisation of travel documents—requires signatory States to implement and maintain a biometric passport system.
ICAO's
mandate for biometric passports derives from Articles 22, 23 and 37 of the Chicago Convention, which oblige Contracting States to develop and adopt international standards for customs, immigration and other procedures to facilitate the border-crossing processes involved in international air transport.
Biometric passports were introduced in the UK in 2006 in line with the ICAO requirements, and, since 2006-03-06, have been the only type of passport issued in the UK.