Investing.com - Oil was lower Wednesday as industry data showed a big build-up in U.S. crude stocks.
Brent crude was off 34 cents, or 0.61%, at $55.63 at 08:30 ET. U.S. crude fell 35 cents, or 0.66%, to $52.85.
The American Petroleum Institute Tuesday reported an increase of 9.9 million barrels in crude stocks in the latest week.
Gasoline and distillate inventories also rose.
Official Energy Information Administration figures due Wednesday are expected to show an increase in U.S. crude stocks of 3.5 million barrels.
The market remains underpinned by signs of OPEC adherence to agreed output cuts.
The cartel is implementing cuts of 1.2 million barrels per day at the start of this year for six months.
Non-OPEC members led by Russia have also agreed to cut production by 558.000 barrels a day.