The December 31 deadline for linking Aadhaar to bank accounts has been extended by the government ahead of tomorrow's hearing of the matter in the Supreme Court. The new date to link the Unique Identification number and the PAN to accounts more than six months old is March 31, 2018.

A government statement said the rule under the 2002 Prevention of Money Laundering Act, had been amended. For accounts opened after June 1, 2017, Aadhaar, Permanent Account Number or PAN and Form 60 will have to be submitted within six months of opening or by March 31, 2018 -- the later date will be the deadline. For older accounts, the deadline is March 31, 2018.

The anti-money laundering law is crucial to combat generation of black money and under it, banks and financial institutions are required to verify the identity of clients. Hence the declaration of Permanent Account Number and Aadhaar number has been made mandatory by the government.

While the 12-digit Aadhaar is issued by the Unique Identification Authority of India, PAN is allotted by the Income Tax Department. Form 60 is a declaration filed by individuals who conduct transactions but do not have PAN.

The government's order comes ahead of the hearing in the Supreme Court tomorrow, in which a five-judge bench is expected issue an interim order regarding a bunch of petitions that demand that the government's move to make the 12-digit Unique Identification number mandatory for bank accounts, financial transactions, cellphones and welfare measures be held off.

Activists have objected against the move, saying it is a breach of the fundamental Right to Privacy. They have also challenged the validity of Aadhaar, which collects and stores biometric data like finger prints and iris scans, saying it might be misused.

Last week, the government had said people who do not have Aadhaar will get another three months to link their Unique Identification Number with bank accounts and government welfare programmes. At the time, the government had said it was willing to extend the mandatory deadline till March 31.