"The memorandum of understanding provides for cooperation in exploration and production for conventional and unconventional petroleum and natural gas opportunities in India and in third countries," the Indian company stated.
The state-owned ONGC said the deal was signed Friday by senior officials from the two companies.
India and Japan are two of the leading natural gas consumers in the world, with the latter seeking more natural gas to offset the loss of nuclear energy from the 2011 meltdown at the Fukushima Daiichi nuclear power plant.
In early January, the ONGC said it expected to produce as much as 353 million cubic feet of natural gas from offshore reserves by 2018.
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