The move is to help cover the cost of providing the city with cleaner but more expensive Euro IV standard fuel, the Beijing Municipal Commission of Development and Reform said in a notice posted on its website (www.bjpc.gov.cn).

Wholesale prices have also been increased.

The price rise only affects Beijing, where city dwellers are more affluent and consumption has been rising quickly. The capital has also been at the centre of government drives to improve energy efficiency and curb pollution.

The increase comes on top of a surprise nationwide hike in June of near 20 percent. But it is not the first time residents of the capital have had to deal with fuel prices rising faster than for their compatriots.

In a nationwide fuel price increase in March 2006, Beijing prices rose more than the national average.

The National Development and Reform Commission, which sets energy policy, explained that move by saying it was more expensive to refine Euro-III standard gasoline for the capital than the dirtier fuel used elsewhere in China.

China's domestic fuel prices have roughly doubled since the start of 2003, although they have lagged global crude markets, forcing refiners Sinopec and PetroChina to shoulder losses on sales of refined fuel.

For a table comparing gasoline prices around the world in September, please click on (Reporting by Emma Graham-Harrison and Tom Miles in Hong Kong; editing by James Jukwey)