ONGC Videsh is to acquire a 25% stake in the Satpayev offshore exploration block in Kazakhstan for an undisclosed sum.

The company signed an agreement with Kazakhstan’s Ministry of Oil and Gas and KazMunaiGaz, the country’s national oil company.

Potential oil resources estimated for the block, which is situated in a highly prospective region of the North Caspian Sea, is 1.8 billion barrels.

The block contains two prospective structures with 256 million tonnes in estimated hydrocarbon resources.

OVL has already got Kazakhstan’s approval to invest $400m in the block and operations are expected to begin by 2020.

The company also signed a participating share assignment agreement, a carry agreement and a joint operating agreement.

Under the terms of the carry agreement, OVL can sell any discovery in the Satpayev block locally.