The PetroChina Co. Ltd., the country's largest oil producer, said on Thursday its net profits edged up 1 percent year-on-year in the first six months of the year to 66.01 billion yuan (10.31 billion U.S. dollars).

The figures were calculated according to international financial reporting standards, the company said.

In the first six months of this year, the company suffered losses of 23.36 billion yuan in the refining business, compared with an operating profit of 5.46 billion yuan in the firm's refining business in the first half of last year, due to high crude prices and domestic government-set retail prices.

However, it said operating profits for the company's exploration-and-production businesses surged 41.3 percent to 103.68 billion yuan as the average selling price of its crude oil climbed 40.3 percent from one year earlier to 101.62 U.S. dollars per barrel.

Boosted by strong energy demand, PetroChina's crude oil output in the first six months rose 5 percent year-on-year to 446 million barrels, while its natural gas production increased 5.3 percent to 1.19 trillion cubic feet.

The company said it sees increasing uncertain and unstable factors in global economic recovery, which will cause fluctuations in the world's financial markets and oil prices in the second half of the year.

Prior to issuing its report, PetroChina share prices surged 2.64 percent in Shanghai to 10.1 yuan and gained 1.82 percent to 9.51 Hong Kong dollars on Thursday.