Senior Supreme Court advocate Prashant Bhushan Sunday said the Rafale deal was the "largest defence scam in India" and urged the Centre to initiate a Joint Parliamentary Committee (JPC) probe into the matter.
Addressing reporters here, he questioned how Anil Ambani's Reliance Defence, the Indian offset partner of French firm Dassault Aviation, could be involved in the project as "most of his companies are in debt."
"This is not only the largest defence scam in India, but is one where national security has been severely compromised. While the IAF wanted 126 flights, it was reduced to 36," Bhushan said.
Prime Minister Narendra Modi had announced the procurement of a batch of 36 Rafale jets after holding talks with then French president Francois Hollande on April 10, 2015 in Paris.
Opposition Congress has accused the government of choosing Reliance Defence over state-run Hindustan Aeronautics Ltd to benefit the private firm though it did not have any experience in the aerospace sector.
Lashing out at Modi and Defence Minister Nirmala Sitharaman, Bhushan charged the Centre with making IAF officials "lie" about the deal.
"You have severely compromised national security, broke the IAF's back, looted people's money and defamed a public sector unit (HAL)," he said.
"The government should immediately agree for a JPC probe and put all the papers before it. There is no (element) of national security (as being claimed by the government). They only want to hide the huge scam in defence purchase," he said.
He further suggested that Ambani's company could not have entered the deal without the defence minister's approval.
Hollande's reported comments that New Delhi had proposed Reliance Defence as the Indian partner for the contract has escalated into a major political row, even as the French government said it had no say in the choice of the Indian industrial partner for the multi-billion dollar deal.
However, Dassault Aviation refuted Hollande's claims and said that it was their decision to partner with Reliance.