Angola’s state-owned oil company Sonangol agreed to acquire Cobalt International Energy Inc.’s 40% interest in its offshore Angolan discoveries for $1.75b, reported Bloomberg.

The sale is supposed to help the company focus on its other assets and exploration operations.

According to Reuters, however, the selling price was below that expected by analysts. RBC Capital Markets had calculated a price range between $2b to $4.5b.

It is interesting in this regard that Cobalt is being investigated by the US Department of Justice and specifically over its Angolan operations, with allegations concerning its partner company in Angola, Nazaki Oil and Gaz, and senior Angolan government officials.

The company is a Houston-based deep-water oil explorer. Cobalt will continue as operator for an interim period with Sonangol bearing all costs. The sale of its stake to Sonangol becomes effective as of January 1, 2015.