Crude oil imports rose 9.8 percent year-on-year in the first four months of this year to 59.77 million tons, the General Administration of Customs said on Tuesday.

But the cost surged to 40.3 billion U.S. dollars, up 80.8 percent, due to higher global crude prices.

China exported 800,000 tons of crude oil, down 25.2 percent in volume, but the export value was up 27.6 percent to 470 million U.S. dollars.

Refined oil imports rose 9.2 percent to 12.68 million tons, while exports totaled 4.84 million tons, down 7.8 percent.

Some areas in China faced diesel shortages while refiners experienced losses resulting from domestic prices that were below world levels, which increased pressure on the government to adjust prices, customs said.

China has imposed price ceilings on domestic refined oil products amid efforts to curb inflation. It also cut import tax rates for most refined oil products from this year to ease supply strains.

The government raised the consumption tax rates on imported oil products such as lubricating oil and fuel oil from March. The move would increase the cost of imported refined oil and optimize the structure of consumption, said the administration.