Addressing the Congress plenary session at Burari in northwest Delhi, Dr. Singh said: "His government would vigorously pursue the investigation into the Commonwealth Games (CWG) and the 2G spectrum allocation scams."

"Inquiries will be pursued vigorously. It is my promise to you that no guilty person will be spared," he added. "We have always strived to eradicate corruption, and the country can rest assure that we will continue to do so in the future," he said.

Rejecting again the opposition's demand for a Joint Parliamentary Committee (JPC) to look into the scam, Dr. Singh said that it is wrong to suggest that the government does not want a JPC because it will have the power to summon him. He said: "I have nothing to hide."

He said that he would write to the chairman of the Public Accounts Committee. He further said,  "I will be happy to appear before it if they ask me to do so, even though there is no precedent to that affect."

Dr Singh also took a shot at the BJP, which has refused to sack Karnataka Chief Minister BS Yeddyurappa despite his being accused of a series of illegal land deals, brokered to benefit his family.

"Charges are being leveled against our party and our government. Our record has been questioned...it is being alleged that we are not sensitive to the issue of corruption," he said.

"On this count...I wish to make our stand clear...we have asked chief ministers to step down merely on the basis of suspicion...we are not like some opposition parties that allow tainted chief ministers to stay in office," he added.