New Delhi - Key Indian stock indices rose by more than 4.5 per cent Thursday, buoyed by an early upward trend in European markets and an announcement by Reliance Industries Ltd that it had started pumping natural gas from a deep-sea basin off the south-eastern coast.

The KG-D6 basin project off Andhra Pradesh state was expected to double India's gas output and save the country 9 billion dollars in oil imports annually.

Reliance Industries led the rise of shares in the Bombay Stock Exchange's 30-share Sensex index, which gained 4.51 per cent to close at 10,348.83. Reliance shares rose by more than 5 per cent.

The National Stock Exchange's broader 50-share Nifty ended at 3,211.05, 4.92 per cent higher.

The market rally was aided by expectations of a further easing of monetary policy by the federal Reserve Bank of India.

Weekly inflation figures, linked to a wholesale price index, also changed only marginally, rising 0.31 per cent in the week that ended March 21 compared with 0.27 per cent the week before.

A consortium made up of Reliance and the Canada-based oil-exploration company Niko Resources Ltd was awarded the KG-D6 block of the Krishna-Godavari basin in the Bay of Bengal under a bidding process. Reliance own a 90-per-cent and Niko 10-per-cent participating interest in the block.(dpa)

"At peak production, the KG-D6 facility is expected to produce over 550,000 barrels of oil equivalent per day," a Reliance Industries release said.

India depends on imports for about 70 per cent of its oil and gas needs.

The initial production of gas would largely be used to provide power to fertilizer firms.

Reliance Industries took six and a half years from discovery to the start of gas production from the deep-sea KG-D6 block, compared with the usual global timeframe of nine to 10 years, the company release added.

So far, two of the 18 gas finds in the KG basin have been put into production.

The field was expected to generate 42 billion dollars in revenues during its estimated 11-year life. The government's share in production would amount to a minimum 14 billion dollars, India's petroleum secretary, RS Pandey, said.

Reliance Industries is one of India's largest privately owned companies with annual turnover of 34.7 billion dollars as of March 2008.