The state-owned firm is seeking up to 520,000 tonnes of high sulphur fuel oil, 165,000 tonnes of low sulphur fuel oil, 305,000 tonnes of 0.5 percent sulphur gasoil, and 315,000 tonnes of 87-octane gasoline.

PSO last bought 840,000 tonnes of fuel oil and gasoline for August-October delivery, skipping gasoil spot purchase. It last bought gasoil in May, for June-August delivery.

The current tender closes Aug. 29, with bids valid until Sept. 7.