Oil prices fell on concerns over the global oil oversupply. According to data by Genscape Inc., crude stocks at the Cushing, Oklahoma, climbed by 1.4 million barrels in the week ending December 15.

Market participants continued to eye yesterday's U.S. crude oil inventories data. According to the U.S. Energy Information Administration's (EIA) data on Wednesday, U.S. crude inventories increased by 4.80 million barrels to 490.7 million in the week to December 11. Analysts had expected U.S. crude oil inventories to decline by 1.4 million barrels.

Gasoline inventories increased by 1.7 million barrels, according to the EIA.

Crude stocks at the Cushing, Oklahoma, climbed by 607,000 barrels.

U.S. crude oil imports increased by 291,000 barrels per day.

Refineries in the U.S. were running at 91.9% of capacity, down from 93.1% the previous week.

A stronger U.S. dollar also weighed on oil prices. The U.S. dollar was supported by the Fed's interest rate hike. Oil suffers when the U.S. dollar strengthens, becoming more expensive for holders of other currencies.

WTI crude oil for January delivery declined to $34.79 a barrel on the New York Mercantile Exchange.

Brent crude oil for January decreased to $37.46 a barrel on ICE Futures Europe.