CHINA'S third-largest oil company, CNOOC Ltd, says it has opened the first gas station of a planned chain, entering a market dominated by its bigger Chinese rivals.

Oil companies and others are racing to cash in on the explosive growth in driving and automobile purchases in China.

CNOOC opened its first station this week in Huizhou, a city in southeast China's Guangdong Province, one of the country's most prosperous areas, the company said on its Website. It said it has received approval to open 20 more stations in the city, home to one of its refineries.

CNOOC said earlier that it planned to open as many as 200 filling stations throughout China.

The retail gasoline market is dominated by China's biggest oil companies, PetroChina Ltd and Sinopec Ltd, each of which has chains of hundreds of filling stations throughout the country.