US-based independent energy company Hess has divested its interests in the ACG fields and BTC pipeline to ONGC for $1bn.

Under the agreement, the India-based multinational oil and gas company ONGC has purchased 2.72% interest in the Azeri, Chirag and Guneshli fields (ACG) and 2.36% interest in the associated BTC pipeline.

The ACG fields are large complex oil fields located in the Caspian Sea about 100km east of Baku, the capital of Azerbaijan.

The oil fields are operated by BP and are in production since 1997.

Hess chairman and CEO John B Hess said the sale of the interest is a part of its business strategy to focus more on higher growth and lower risk pure play exploration and production.

"Consistent with our announcement on March 4, the after tax net proceeds from this sale will be used to pay down an equivalent amount of short term debt," Hess added.

The after tax net proceeds are $884m.

Crude oil produced from the ACG fields is exported through the 1,768km long Baku-Tbilisi-Ceyhan (BTC) pipeline to the Mediterranean Sea.