The government may issue an ordinance to provide clear legal support for extinguishing the demonetised Rs 500 and Rs 1,000 notes that are not returned by December 30. The government wants to amend the Reserve Bank of India Act to this effect and ordinance route may be opted for as Parliament would not be in session immediately after the last day of surrender.The ongoing winter session of Parliament — disrupted by protests as it has been — ends December 16 and the budget session will start only late January.

Source - http://economictimes.indiatimes.com