China and the US should jointly develop oil fields to protect against supply risks and rising production costs, a senior Chinese official said Monday. Zhang Guobao, vice chairman of the National Development and Reform Commission, made the comments days ahead of a planned meeting between top US and Chinese energy-policy makers, the Wall Street Journal reported. There is concern in the US that Chinese state energy companies are pursuing an aggressive overseas oil acquisition strategy in order to meet growing domestic demand. The Chinese companies do business in countries blacklisted by the US, such as Sudan and Iran, often sweetening deals with funding for infrastructure projects. China's energy push is likely to share top billing at the meeting with discussions on the country's management of its domestic oil market. Without warning or specific details on its calculation, Beijing imposed a windfall energy tax on both foreign and domestic companies last March.