BEIJING (AFX-ASIA) – China National Petroleum Corp (CNPC), the parent company of PetroChina Co Ltd (HK 0857; NYSE PTR), said it is unaware that Ma Fucai, chairman of PetroChina and president of CNPC, has resigned. “I am unaware of Mr Ma’s departure, we have not received any official notice so far,” CNPC spokesman Fu Zhongkai…