NDA today demanded resignation from the Prime Minister if he is against a JPC probe in the 2G Spectrum issue. Addressing a rally in New Delhi today, the NDA leaders urged the Prime Minister to form the JPC and answer the questions of opposition.They maintained that his offer to appear before the Public Accounts Committee is not enough and renewed their demand of JPC probe.Addressing the rally, senior BJP leader LK Advani described the campaign against corruption as a campaign against the Prime Minister. Several other NDA leaders addressed the rally. The Congress on the other hand rubbished the BJP demand for Prime Minister's resignation.Briefing reporters, the party spokesman Abhishek Singhvi held opposition responsible for Logjam over the issue in parliament. He added that a mulit-agency probe is already on to look into the spectrum allocation.