BEIJING - Sinopec Corp, Asia's largest oil refiner, said Thursday that its net profit slumped 35.04 percent year on year to 13.41 billion yuan ($2.13 billion) in the first quarter amid rising operation costs and diminishing profit margins.

Business earnings during the period dropped 28.99 percent year on year to 21.81 billion yuan, the company said in its quarterly report filed with the Shanghai Stock Exchange.

The company said its output of crude oil and natural gas saw steady growth due to a smooth exploration process, rising 4.47 percent to 81.53 million barrels and 11.77 percent to 4.05 billion cubic meters, respectively.

Meanwhile, the company processed 55.41 million tons of crude oil during the period, with the output of refined oil gaining 5.01 percent to 32.87 million tons, according to the statement.

The company said the gap between international oil prices and prices at home created 9.17 billion yuan in losses in its refining sector.