New Delhi, (PTI) Asserting that the government has launched a "crusade" against corruption and black money by demonetisation, Prime Minister Narendra Modi today sought opposition's cooperation while his rivals called the decision ill-prepared and hasty, causing "economic chaos".

Leader of the Opposition in the Rajya Sabha Ghulam Nabi Azad alleged the decision to invalidate Rs 1000/500 currency notes was leaked in advance to some people, including BJP leaders, and called it probably the "biggest scam".

He, however, added that his party is not for its rollback.

In his concluding remarks at the all-party meeting on the eve of the Winter Session, Modi spoke in support of simultaneous Lok Sabha and state assemblies polls and that there should be state-funding of elections as he asked parties to debate the issue.

The government is willing to discuss all issues and answer the questions raised by the opposition, Modi said, hoping for a fruitful session as he recalled the passage of the GST Bill in the last session with the cooperation of all parties.

"We have launched a crusade against corruption, black money and fake currency, which is also behind cross-border terrorism. All parties should come together on this issue of national interest," he said.

Parliamentary Affairs Minister Ananth Kumar briefed the reporters about Modi's remarks.

Speaking about simultaneous polls, he said, "A crucial problem is how to make political funding transparent. How to implement state funding of elections. Let all political parties debate it and come to a conclusion. Let's remove the question mark which exists against those in public life.

"Polls happen separately. Let there be one election, simultaneous elections," he said, seeking a consensus on the issue.