The Immigration and Checkpoints Authority (ICA) will be collecting iris images from Singaporeans and permanent residents from next month, as amendments to the National Registration Act kick in.

The iris images will serve as another identifier, in addition to photographs and fingerprints, the Ministry of Home Affairs (MHA) said in a statement yesterday.

This will be done as part of the National Registration Identity Card (NRIC) registration and re-registration process, and passport application and renewal.

Amendments to the Act were passed last month and are aimed at strengthening "the effectiveness and efficiency of (ICA's) operations", said MHA.

Senior Minister of State for Home Affairs and National Development Desmond Lee had told Parliament that the collection of iris images would be done in preparation for a roll-out of iris-scanning technology at land, air and sea checkpoints in the next two years.

The collection and verification of iris images is a non-intrusive process similar to taking a photograph.

The amendments will allow the ICA to collect more forms of personal identification data but not body samples, such as blood, through invasive means.

The ICA had received feedback from people who had problems using automated clearance gates at checkpoints because of difficulties in producing definitive fingerprints.

Iris scanning has been used in the Netherlands and Germany since the early 2000s, while the United Arab Emirates has mandated the collection of iris images from all citizens since 2013.

Selected SingPost employees will also be appointed as registration officers to assist NRIC holders at certain outlets. SingPost outlets are another location where passports, identity cards and long-term passes can be registered.

Principal research analyst Anmol Singh of market research firm Gartner said that collecting iris scans will provide an additional level of security. Such scans are convenient to collect and identify on the spot. The process is contactless, so users can avoid infections which may be passed through surface contact.

"(Iris images are) a more stable biometric feature compared with fingerprints, which change more rapidly in the ageing process and may require more frequent re-enrolment," he said.

Mr Nick Savvides, security advocate at Symantec, said: "Some consumers have difficulty with fingerprint scanners because of shallow prints, finger injuries or other biological reasons."

But Mr Aloysius Cheang, executive vice-president of global computing security association Cloud Security Alliance, cautioned that iris images may not necessarily provide a "significant improvement in the level of security" from fingerprints as the files could still be hacked.