Oil prices declined on Thursday, after the International Energy Department reported a bearish outlook of the market.

The Energy Department on Thursday lowered its forecast for oil demand for 2018.

"Our forecast of global demand growth remains unchanged at 1.6 million barrels per day in 2017, or 1.6 percent, and 1.4 million barrels per day in 2018, or 1.4 percent," said the report.

Meanwhile, traders also focused on oil inventory data.

Crude oil inventories fell 2.7 million barrels in the October 6 week to 462.2 million, 2.5 percent below the level a year ago, the Energy Information Administration (EIA) said in its weekly report Thursday.

The West Texas Intermediate for November delivery decreased 0.70 U.S. dollar to settle at 50.60 dollars a barrel on the New York Mercantile Exchange, while Brent crude for December delivery lost 0.69 dollar to close at 56.25 dollars a barrel on the London ICE Futures Exchange.