Men work on an oil pump during a sandstorm in the desert oil fields of Sakhir, Bahrain, January, 2015.

Oil slumped to a two-week low on Wednesday, after U.S. data showed a smaller-than-expected drop in overall crude stocks and a surprising build in gasoline inventories, which raised worries about excessively high global supply.

U.S. crude futures settled down $1.97 to $50.44 a barrel, a 3.8 percent drop, the worst-one day decline since March 8, as investors bailed out of long positions in response to the bearish inventory figures.