KNOC is likely to finalise purchase details of the cargo prices in late October. It may seek another 100,000 barrels of the motor fuel at a later date, but the exact schedule has not been decided.

With South Korea, Asia's fourth-largest economy, heavily dependent on oil imports, its government has been helping retailers expand the number of petrol stations that undercut pump prices by receiving auto fuel, mainly from KNOC.

KNOC imports or buys gasoline domestically.

In February it bought 300,000 barrels of gasoline for delivery in December and it was already planning to buy at least 100,000 barrels more in October.