Investing.com - Oil prices declined on Wednesday, amid speculation weekly supply data due later in the session will show U.S. crude inventories rose for the ninth straight week last week.
U.S. crude was last down 1.2% at $42.37 a barrel, while Brent dropped 1.1% to $45.61.
The U.S. Energy Information Administration will release its weekly report on oil supplies at 10:30AM ET. The data was expected to show that crude inventories rose by 1.2 million barrels last week.
After markets closed Tuesday, the American Petroleum Institute, an industry group, said that U.S. crude inventories rose by 2.6 million barrels in the week ended November 20.
U.S. oil supplies have risen for eight straight weeks, underlining concerns over a domestic supply glut.
The oil market has been volatile in recent months amid uncertainty about how quickly the global glut of crude is set to shrink.