New Delhi, July 20 - The raging dispute being heard in the Supreme Court between the companies belonging to the two Ambani brothers, Mukesh and Anil, mainly concerns the supply and pricing of natural gas from the Krishna Godavari basin.

At the core of the dispute is how valid is a family pact reached between the two brothers, brokered by their mother Kokilaben when the Reliance empire was split a few years ago, in deciding the price of gas in which the government, too, has claimed a share.

The fields, off the Andhra Pradesh coast, were won by Mukesh Ambani-led Reliance Industries, and are one of the biggest discoveries made in Asia in recent years. Anil Ambani wants a part of the gas for his group's power plants, based on the family pact.

But the ministry of petroleum and natural gas is not happy with the price at which Anil Ambani has asked for the gas -- between the time the family pact was reached in 2005 and now, hydrocarbon prices have more than doubled.

The government, based on the recommendations of a committee led by the present Finance Minister Pranab Mukherjee, had recommended the price of natural gas from the Krishna Godavari basin at $4.