The Indian-operated Farzad field in Iran's Farsi block is expected to produce about 9.7 trillion cubic feet (TCF) of gas in 30 years, India's junior oil minister Jitin Prasada said on Monday.
Farsi is the first overseas asset for which India firms have obtained exclusive exploration rights.
India's state-run Oil and Natural Gas Corp (ONGC.BO) and Indian Oil Corp (IOC.BO) each hold a 40 percent interest in the block, and smaller outfit Oil India Ltd has the rest. The Persian GUlf block is operated by ONGC's overseas arm, ONGC Videsh Ltd.
"The potential of the gas production from Farzad-B gas field in 30 years is about 9.7 TCF," the minister told parliament in a written reply.
ONGC Videsh Ltd has submitted a master development plan for the Farzad-B gas field in Persian Gulf to the Iranian Offshore Oil Co (IOOC) in line with the exploration service contract, the minister said.
"The amount of the investment will depend on the approval of master development plan by Iranian authorities," the minister said.
News reports earlier said Indian firms plan to spend around $5 billion to develop the offshore Farzad gas field and ship the liquefied natural gas (LNG) to India.
"Since the Farsi block is being operated by ONGC Videsh under exploration service contract, the amount of gas has not been committed to ONGC Videsh," Prasada said.
In November 2008, a senior source at an Indian company holding a stake in the block said Iran had approved the commercial viability of natural gas production at the Farsi block.
Iran is drawing interest from Indian and Chinese firms that are keen to tap the world's second-largest reserves of oil and gas and are less susceptible than many other companies to Western pressure over Tehran's nuclear programme.
The minister said at present Indian national oil companies were not competing with China to acquire oil fields in Iran, but competition could not be ruled out in future.
India, which imports over 70 percent of its oil requirements and is Asia's third-largest oil consumer, has been intensifying its efforts to boost oil production abroad to make up for stagnating domestic output.