'NTPC should take all possible steps to protect its interest as advised by the solicitor general,' said Vahanvati over the weekend, endorsing the solicitor general's legal opinion to the government.

Law ministry officials said the unanimous opinion of the two law officers has been forwarded to NTPC, which is a listed company that has 10.5 percent of its shares held by public and financial institutions.

'The fact that NTPC had to file a suit is a telling comment on the facts of the present case,' said Subramaniam.

'I regret to say that if international competitive bidding processes are intended to be treated with such disdain from responsible bidder (Reliance Industries), the world of business founded on trust and faith will break down.'

NTPC - as also Anil Ambani's Reliance Natural Resources - are fighting a legal battle to get gas at $2.34 per unit from Reliance Industries, which has refused to do so, saying the government's stand on price would frustrate the deal.