Angolan state oil company Sonangol has discovered gas reserves in the offshore Kwanza Basin that it says could total 813 million barrels of oil equivalent (MMboe).

The reserves were discovered in a block in which BP Plc (NYSE: BP) has a stake.

Sonangol said Block 20/11 held an estimated 313 MMbbl of condensate and 2.8 trillion cubic feet of gas.