Cairn India and its joint venture partner Oil and Natural Gas Corporation (ONGC) will invest Rs200bn ($4bn) by 2011 to boost production at Barmer oil fields in the Indian state of Rajasthan, Cairn has announced.

The investment at the Mangala, Bhagyam and Aishwariya fields is aimed at increasing production by 25,000bpd to 200,000bpd, and will be shared between Cairn India (70%) and ONGC (30%), according to the Economic Times of India.

The fields have a 2P recoverable resource of almost 700 million barrels of oil with an additional 300 million barrels of enhanced oil recovery potential.

The Mangala processing terminal would begin crude production by the end of this month, with an initial capacity of 30,000bpd, which would be increased to 100,000bpd by 2010.

Cairn India has finalised commercial terms and pricing negotiations with the Indian Oil Corporation and the Mangalore Refinery and Petrochemicals for 2009-10 and 2010-11.