The Unique Identification Authority of India (UIDAI) has issued its 3.5 millionth identification number under Aadhaar, nearly six months after the launch of the world's largest biometrics-based identity programme.

Prime Minister Manmohan Singh and UPA chief Sonia Gandhi had rolled out the ambitious project, where biometric data is used to provide unique identification numbers to India's billion-plus citizens, from Tembhli village in north Maharashtra's Nandurbar district on September 29 last year, by handing over the first set of 12-digit numbers to 10 tribals.

Technology provider Morpho said its technology has enabled UIDAI meet this landmark, adding that UIDAI plans to issue 600 million Aadhaar numbers over the next four years.

The company's latest-generation technology has played a pivotal role in the programme for de-duplication of the biometric records enabling issuance of unique identification numbers, it said.

The Aadhaar project aims to deliver a unique number to each Indian resident, which will provide highly secure access (using fingerprint and iris recognition) to a wide range of benefits and services.

"We are truly proud that our cutting-edge biometric technology has allowed the UIDAI to reach the two million milestone in this large-scale project," Jean-Paul Jainsky, chairman and chief executive officer of Morpho, said.

"This achievement highlights the efforts and commitment of all the partners involved to make the Aadhaar programme a success," he added.