India's top court on Wednesday ordered the government to provide pricing details of 36 Rafale fighter jets it is buying from France.

The court said the government must bring details of the decision-making process of the deal into the public domain, except those that are confidential and have strategic importance. The court said those can be provided in a "sealed cover" within 10 days.

The deal has become a major political issue with the leader of the main opposition Indian National Congress party, Rahul Gandhi, accusing Prime Minister Narendra Modi's government of buying the aircraft at nearly three times the price being negotiated when his party was in power before Modi became prime minister in 2014.

The government has refuted the claim, but says a secrecy clause governs the deal's pricing. It hasn't even informed Parliament about the cost of the 36 planes.

The court was hearing petitions by former ministers Arun Shourie and Yashwant Sinha and some others who demanded a court-monitored probe by a federal investigating agency in the deal.

Gandhi also accused Modi's government of favoring the company owned by industrialist Anil Ambani, Reliance Group, when choosing an Indian partner for Dassault.

India's government has denied any wrongdoing. Dassault Aviation recently said that it "has freely chosen to make a partnership with India's Reliance Group."

The French company said that it had committed to side deals in India worth 50 percent of the value of the jet purchases. In order to deliver those side deals, it had decided to create a joint venture with Reliance Group.

The controversy has intensified following comments last month by former French President Francois Hollande — who was in charge when the deal was signed in 2016 — suggesting France had no say in selecting the Indian company.