It is still unclear why the ministry did not fully disclose the formula approved by the eGoM on 12 September or why it did not respond to specific, repeated queries on the issue from Mint earlier this week.

RIL, for its part, had also declined to comment on the issue. The company spokesperson could not be reached for comment till late Tuesday.

Meanwhile, political parties reacted strongly to the government's failure to clearly disclose the underlying issues involved in the gas pricing.

"How can the ministry's note not clearly reflect the decision of the eGoM? How can the ministry keep the country in the dark?" asked D. Raja, national secretary of the Communist Party of India, which supports the ruling Congressled government at the Centre.

Yashwant Sinha, a former finance minister and a Rajya Sabha member of the principal opposition, the Bharatiya Janata Party, maintained that the government had "deliberately misled" the nation.

"If the government had the courage of conviction, it wouldn't have concealed this vital piece of information in the press note," said Sinha.

"The omission puts a question mark on the decision simply because the government chose not to be upfront about it."

A spokesperson for the Congress party couldn't immediately be reached for comment.

Tapan Sen, a Rajya Sabha member of the Communist Party of India (Marxist), the largest of the four Left parties that provide a critical outside support to the United Progressive Alliance government, said he had written several letters, without a single response, to the Prime Minister's Office pleading that gas prices should not be linked to international crude prices.

"Unfortunately, the bids are always non-transparent and not cost-based," he said. "Adding more variablity to the existing equation will only leave the state-owned consumer, National Thermal Power Corp.(now NTPC Ltd), the worstaffected."

Swadesh Dev Roye, national secretary of CPIM-backed Centre of Indian Trade Unions (Citu), said the formula had too many variables, including global crude prices. "Now that the government's press release and the eGoM's decision don't appear to match, it seems the ground is being prepared for a further hike in prices. This will impact domestic consumers, specially crucial industries such as power and fertilizers, in a big way."

However, market players welcomed the government's decision to not cap gas prices and instead fix a floor.

"We knew that the prices would go up. The fact that there is no cap is a good thing for Reliance," said a Mumbaibased investment banker who did not wish to be identified.

On the Bombay Stock Exchange, RIL shares rose 1.5% to Rs2,058.40 on a day when the Sensex was up 1.06%.