Global demand for oil from OPEC next year will be less than expected because of weaker growth in consumption and the U.S. shale boom, the group said on Wednesday, pointing to an increasing supply surplus in 2015.
In a monthly report, the Organization of the Petroleum Exporting Countries (OPEC) forecast demand for the group's oil will drop to 28.92 million barrels per day (bpd) in 2015, down 280,000 bpd from its previous expectation.
Brent crude oil slipped below $66 a barrel on Wednesday, just above a five-year low, after the report was out.
The report follows OPEC's decision last month not to cut output despite plunging prices, as top exporter Saudi Arabia urged fellow members to combat the U.S. shale oil boom which has been eroding OPEC's market share.
The price of the North Sea oil benchmark has fallen more than 40 percent since June as new supplies of high-quality crude from North America have fed a glut in many parts of the world.