Until the late 1990s, China supplied its oil needs from domestic sources including the vast Daqing field in the northeast. But the economic boom outstripped its production capacity while output from existing sources is forecast to decline.
That has forced China to rely more heavily on imports, especially from Saudi Arabia and Iran. Communist leaders see that as a strategic weakness because of possible instability in the Gulf and Iran's political isolation.
EIA noted that China's domestic oil production was hampered over the past two months by summer flooding.
State-owned oil companies and their foreign partners are spending heavily to look for new oil sources in China and to develop alternatives such as methane from coal beds. But they have yet to find new deposits that match the size of Daqing.
Abroad, Chinese state-owned oil companies have invested billions of dollars to develop oil and gas sources in Iraq, Central Asia, and Africa. Some of that is meant for export to China but much of it is sold in other markets.
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At the same time, U.S. import demand has weakened as hydraulic fracturing and other technologies open up new domestic sources of supply.
American demand for oil and other liquid fuels rose by about 110,000 barrels per day, or just 0.6 percent, in the first nine months of this year, due partly to improved engine efficiency, the EIA said. It said consumption is forecast to fall by 0.4 percent next year.
Overall, the United States still should be the biggest oil consumer next year at about 18.7 million barrels per day, down from its peak of 20.8 million in 2005, according to the EIA. It said China's consumption next should be about 11 million barrels per day.
—By The Associated Press