The fuel surcharge that international flight passengers have to pay is expected to be lowered to zero in South Korea for the first time in six years next month as global oil prices continue to drop, industry sources said Monday.

The surcharge system allows air carriers to adjust the extra fees for international and domestic routes each month in tandem with changes in the average price of fuel traded via Singapore's spot market.

The surcharge is not levied if the average fuel price falls below $1.5 per gallon. The latest data showed that the average fuel price measured between July 16 and Aug. 15, a basis period for determining the amount of surcharge in September, stood at $1.46.

As a result, passengers purchasing international flight tickets for September will not pay any fuel surcharge, the sources said. In August, airlines here are levying around 16,000 won ($13.6) on international flights.

It would be the first time that the fuel surcharge has fallen to zero since August 2009.

For domestic routes, the surcharge is expected to be lowered from 3,300 won in August to 2,200 won next month. The domestic flight surcharge is based on the average fuel price between Aug. 1-31. (Yonhap)