China National Petroleum Corporation (CNPC), the country's largest oil and gas producer and supplier, reported a profit decline in the first three quarters of 2019 despite rising sales revenue.

During the January-September period, the company raked in total revenue of 1.81 trillion yuan (about 256.9 billion U.S. dollars), up 5.1 percent year on year, according to the CNPC's report filed to the Shanghai Stock Exchange on Wednesday.

Net profits attributable to shareholders during the same period dropped 23.4 percent year on year to 37.25 billion yuan, the report said.

"The decline was due to the downward trend of the international oil price and fierce competition in the domestic market," the report said.

In Q3 alone, basic earnings per share dropped 58.4 percent year on year to 0.048 yuan, the statement said.

CNPC shares on the Shanghai Stock Exchange dropped 0.83 percent on Wednesday to 5.98 yuan.