The American Petroleum Institute (API) on Tuesday reported an increase of 3.69 million barrels of crude oil in U.S. inventories for the week ending May 12.
Analysts had expected a drop of 1.3 million barrels for this week.
The API reported a decline of 3.618 million barrels in the previous week.
Oil prices declined on Tuesday. The West Texas Intermediate for June delivery fell 25 cents to settle at 70.86 U.S. dollars a barrel on the New York Mercantile Exchange.
Source: Xinhua