Oil Prices Plunge as US Supplies Rise to New Record

Dan Bannister | Image Source | Getty Images

Oil futures tumbled over three percent Wednesday after the U.S. Energy Information Administration reported crude oil supplies at the highest level on record, with a weekly gain that far exceeded expectations.

Brent crude futures fell below $100 a barrel while WTI oil prices saw the largest one-day percentage slide since November, breaching the 50-day moving average to trade below $90.50 a barrel.

The EIA reported weekly U.S. oil inventories rose by 6.7 million barrels, nearly five times greater than the consensus estimate of Platts survey of analysts of a 1.4 million barrel increase. The growth in crude oil supplies in the EIA report also exceed the 5.2 million barrel build in crude oil inventories reported by the American Petroleum Institute Tuesday afternoon.

(Read More: Gas Prices Dip to 3-Year Low Ahead of Summer: AAA)

The EIA also reported gasoline demand slumped 3.6 percent last week. RBOB gasoline futures are also down more than 3 percent at $2.71 a gallon.

While weak data on manufacturing in China and U.S. initially spurred the sell-off in the petroleum markets this morning, Citi Futures energy futures specialist Tim Evans says the weakness in oil is "more closely tied to weak physical demand for products and bearish U.S. inventory data."

(Read More: Where Do Drillers Smell Profits? Think Oil, Not Gas)

—By CNBC's Sharon Epperson; Follow her on Twitter: @sharon_epperson