BP has promised an increase of up to 60% in production of oil and gas output from the Mumbai High field, discovered in 1974, ONGC said in a stock exchange filing.
The field reached a peak production level of 471,000 barrels per day of oil in March 1985, and its output had declined to about 134,000 bpd in April 2024, according to the tender document floated last year.
India, the world's third-biggest oil importer and consumer, wants to quickly raise its oil and gas output, which has been stagnant for years.
In June, the government said that ONGC was seeking a technical tie-up with a global oil major to boost production and BP's board had met India's Oil Minister Hardeep Singh Puri in September 2024.
The country has been asking foreign companies to participate in India's exploration programmes, Puri had said last year.
BP will act as a technical service provider for the field.
"We look forward to bringing our long experience of optimising performance and recovery from major mature fields around the world to help unlock and enhance production from Mumbai High," BP said in a statement.
BP, in a tie-up with Reliance Industries (RELI.NS), opens new tab, operates 1,900 fuel retail stations across India and produces oil and gas from a deepwater block in the Krishna-Godavari basin, off the country's east coast.
The Reliance-BP tie-up has teamed up with ONGC to bid for exploration rights for an offshore block in India.
