The ministry is approaching the Cabinet to allow private companies take 60 per cent stake in producing oil and gas fields of national oil companies, ONGC and OIL, with the view that they would raise production above the baseline estimate.

As many as 15 fields - 11 of Oil and Natural Gas Corp (ONGC) and four of Oil India Ltd (OIL) - with a cumulative in place reserve of 791.2 million tonnes of crude oil and 333.46 billion cubic metres of gas have been identified, sources privy to the development said.

These include Kalok, Ankleshwar, Gandhar and Santhal - the big four oilfields of ONGC in Gujarat.

All of these fields are in blocks or areas that were given to the national oil companies on nomination basis and the current policy does not allow private firms taking equity stake in a nomination block.

So, a change in policy is required for which the ministry is approaching the cabinet, the sources said.

The policy currently allows giving out of participating interest (PI) or a stake to a private company only in the blocks or areas awarded in open auctions under New Exploration Licensing Policy (NELP) since 1999.

However, only exploration acreage was auctioned under global bidding in such rounds. All areas prior to that were given to ONGC and OIL on a nomination basis.

A baseline based on current oil and gas production from the 15 identified fields would be set and private companies taking 60 per cent equity stake would get only the incremental volumes, sources said.

The fields would be auctioned and any firm committing the maximum capital investment within 10 years of the contract award and the largest share out of its net revenue to the government would be awarded the field.

The 15 fields selected are out of a review of 202 fields operated by the national oil companies. The fields chosen are ones that hold reserves of 20 or more million tonnes of oil equivalent (MT OE) and have crossed the half-way mark on a score (indicative of poor field performance) combining exploration index, current recovery, and production decline rate in the last three years.

Of the 202 fields, 141 are either less than 10 years of age or had shown some positive change in the year-on-year production rate.

As many as 44 fields of ONGC and OIL have been identified for production enhancement work through Technical Services Model where technical tie-ups would get the 'tariff' that they bid as a return for increasing the output 'over the baseline production' for 10 years initially.

Sources said the ministry is unhappy with the near stagnant oil and gas production and believes giving out the discovered fields to private firms would help raise output as they can bring in technology and capital.

It has been tasked by Prime Minister Narendra Modi to cut oil import dependence by 10 per cent by 2022 over 77 per cent dependence in 2014-15. The dependence has only increased and is now over 80 per cent.

The privatisation is repeat of the infamous round in 1992-93 when medium sized discovered fields like Panna/Mukta and Tapti oil and gas field in the western offshore was given to now-defunct Enron Corp of the US and Reliance Industries. As many as 28 fields were then awarded.

Under this regime, ONGC was made licensee and given an option to farm-in 40 per cent of the stake.

The controversial privatisation under the then oil minister Satish Sharma had resulted in a CBI inquiry.