SHANGHAI, Dec. 20 (Xinhua) -- Chinese companies' overseas equity oil yield is expected to exceed 200 million tonnes in 2018, almost equaling China's domestic annual oil output, an executive with the China National Petroleum Corporation (CNPC) said Wednesday. "China's oil and gas companies have increasingly expanded presence in Belt and Road countries, making progress in resource exploitation, oil-gas pipeline construction and industrial chain layout," said Qian Xingkun, deputy head of the Economic and Technology Research Institute under the CNPC, at the 2017 China Oil and Gas Reform Summit. According to a report released by the China Petroleum Enterprise Association, investment and output of Chinese oil and gas companies in Belt and Road countries accounted for over 50 percent of their total overseas investment and production respectively. "China is expected to increase its dependance on oil and gas imports for a considerable time to come, thus cooperation in the field will remain important between China and the Belt and Road countries," said Zang Jianjun, executive director of the China CEFC Energy Company.