Investing.com - Oil was flat Tuesday ahead of the release of U.S. stockpile data as U.S. output is expected to rise.
U.S. crude was off 39 cents, or 0.74%, at $52.26 at 08:00 ET. Brent crude shed 50 cents, or 0.90%, to $54.86.
The American Petroleum Institute Tuesday is due to release U.S. crude stocks for the latest week.
These will be followed Wednesday by the Energy Information Administration's U.S. inventories report.
The EIA is expected to report a fall of 1.5 million barrels in U.S. crude stocks.
The EIA on Monday forecast U.S. shale output would post its biggest monthly gain in over two years in May.
The market remains underpinned by hopes of an extension of output cuts by major producers.
OPEC and non-OPEC producers are cutting production by 1.8 million barrels a day in the first half.