The American Petroleum Institute (API) on Tuesday reported a surge of 11.900 million barrels of crude oil in U.S. inventories for the week ending Nov. 3.
Analysts had expected a decline of 0.300 million barrels for this week.
The API reported a hike of 1.347 million barrels in the previous week.
Oil prices fell on Tuesday. The West Texas Intermediate (WTI) for December delivery lost 3.45 U.S. dollars, or 4.27 percent, to settle at 77.37 dollars a barrel on the New York Mercantile Exchange.