By Li Hongmei

Liao Yongyuan was appointed president of China National Petroleum Corporation - China's largest oil and gas company, which trades as PetroChina. He will take over the No. 2 position left vacant by the newly appointed chairman Zhou Jiping, ending two months of uncertainty, reports the Chinese-language Beijing News.

The changes at the state-owned company's leadership come after former chairman Jiang Jiemin was appointed as head of the Assets Supervision & Administration, which oversees more than 100 of China's largest state-owned companies, including CNPC.

Liao, 51, was promoted from the company's vice president. Asked in October last year to comment on the competition between CNPC and rival Sinopec Group, Liao said, "We have no competition, but only cooperation."

Liao's area of expertise is reported to be upstream oil and natural gas exploration, and he is not directly involved in the company's sales or international strategy.

Early this year, CNPC announced that it aims to develop into a world-class international energy company by 2020. Its overseas oil and gas production will account for 60% of its total production and it also aims to increase its domestic market share.