We thank Mr Victor Lim for his letter (Indicate old passport number when new one is issued; Sept 5).

The Singapore Biometric Passport (BioPass) complies with the standards and requirements set by the International Civil Aviation Organisation. This includes having a unique number for every passport issued.

The unique passport number helps to curb abuse of passports when they are lost or stolen, through sharing of the passport number and other relevant information among law enforcement agencies internationally. It is important to ensure the integrity and security of passports.

Nevertheless, we recognise that some Singaporeans may want their previous passport's number to be indicated somewhere in their new passport, for example, for easier reference by certain authorities who might have used the previous passport number as an identifier.

The Immigration and Checkpoints Authority (ICA) can assist with this.

Serene Wong (Ms)

Head, Public & Internal Communications

Corporate Communications Division

Immigration & Checkpoints Authority