A number of Chinese airlines have raised the fuel surcharge on domestic flights to an historic high despite a drop in international oil prices, China Business News (CBN) reported Tuesday.

Air China, China Eastern Airlines, China Southern Airlines and a number of other carriers will increase the extra charge for domestic routes longer than 800 kilometers from 140 yuan ($20.82) to 150 yuan per passenger from Aug 1, reports 163.com, citing Chinese travel website ctrip.com.

The fuel charge for routes shorter than 800 kilometers will remain at 80 yuan per passenger.

The move comes after airlines were informed by the Civil Aviation Administration of China that from Aug 1, factory price of domestic oil is set at 7,725 yuan per ton and the purchase cost for domestic airliners to buy oil from China National Aviation Fuel for their domestic flights was adjusted to 7,785 yuan per ton, the report said.

This is the first-released domestic aviation fuel price after the National Development and Reform Commission published the new pricing mechanism last month.

Although oil prices in the international crude oil market decreased, domestic oil prices rose against trend. An anonymous analyst told the CBN that the CIF (cost, insurance and freight) value of imports for aviation fuel was taking Singaporean oil price as a standard, which was rising.

A senior official with an airline company told CBN that raising fuel surcharge could not fully cover the rise in fuel cost. The profit margin of airline companies would finally be decided by the market demand and ticket prices.

Wu Yunying, an analyst with Changjiang Securities pointed out that as high-speed railways are not taking as many as passengers as expected and the peak season for aviation is approaching, airliners are likely to increase both the amount of passengers and ticket prices.