New Delhi, March 16 (IANS) Finance Minister Arun Jaitley on Wednesday told the Rajya Sabha that Aadhaar card is not mandatory as it was an "entitlement" in a 2010 law and remains the same even in the new law passed by the Lok Sabha.

But despite his clarification, the upper house sent back the Aadhaar (Targeted Delivery of Financial and Other Subsidies, Benefits and Services) Bill, 2016 back to the lower house with four amendments.

"Where people don't have it, alternative documents will be prescribed so there are alternative documents and the user would be predominantly through the state government," Jaitley said.

"Tomorrow, if Tamil Nadu government decides that people below a certain income would get some benefits, then it is mandatory if you want benefits," he said by giving an example.

The Bill, which will give central agencies access to the world's biggest biometric database, was debated in the Rajya Sabha before being sent back to the Lok Sabha on the last day before an an inter-session break.

The Rajya Sabha has a limited role in the passage of a money bill, as the Aadhaar bill has been designated, and can only suggest amendments, which may be accepted or rejected by the Lok Sabha.

In case amendments are recommended, the bill will remain pending unless the process is completed in the Lok Sabha.