On Tuesday evening, after a focused and united attack from opposition parties, the government agreed to a debate in both Houses, but without a vote at the end of it. "The government is ready for discussion on the issue in both Houses of Parliament," said Minister of State for Parliamentary Affairs Rajiv Pratap Rudy.

The discussions have been listed in Wednesday's agenda for the afternoon - under Rule 193 in the Lok Sabha, as well as in the Rajya Sabha. Both entail discussions without a vote.

The Trinamool Congress and the Janata Dal United, the key players behind the opposition attack on the black money issue, are expected to grumble. They have insisted that there must be a discussion with a vote.

The government's hand was forced on the issue by a united Opposition stalling Parliament for some time on Tuesday, the first working day of the winter session. They have accused Prime Minister Narendra Modi of reneging on his election promise of bringing back crores stashed by Indians abroad.

"100 days are over, where is the black money?" chanted members of the Trinamool Congress, Congress, RJD, Samajwadi Party and AAP in the Houses. They trooped into the well of the Lok Sabha over the issue.

Members of Mamata Banerjee's Trinamool Congress blocked the main entrance of Parliament Building, holding up black umbrellas with "Kala Dhan (black money)" written on them.

Samajwadi Party chief Mulayam Singh Yadav also joined the protest briefly. "The Congress government at least gave black money figures. They are not even saying how much there is. They promised to get back black money in 100 days, now it has been six months," Mr Yadav said.

"We had promised to take concrete steps to bring back black money. We have taken steps. That everyone knows. What did the Congress do to bring back black money," said Parliamentary Affairs Minister M Venkaiah Naidu outside Parliament

In the winter session, Opposition parties plan to coordinate efforts to block key legislation in the Rajya Sabha, the upper house of Parliament, where the government is in a minority. Among major bills that the government wants to push through is its big reform, the Insurance Bill.