U.S. crude oil production levels weighed on the minds of investors early Friday, sending oil prices lower as OPEC monitors compliance with a production deal.

In a weekly status report, the U.S. Energy Information Administration reported a slight gain in crude oil inventories as 600,000 barrels. That's opposite of what the industry reported and, while only a minor increase compared with recent weeks, storage levels are still above the average range for this time of year.

The Organization of Petroleum Exporting Countries in January started implementing a production arrangement aimed at offsetting the surplus. Surveys from early February found compliance from the 10 contributing OPEC members at 91 percent. A monitoring committee from OPEC said Friday that total compliance in January, including non-OPEC contributors, was 86 percent.

Crude oil prices moved sharply higher early Thursday on the back of industry reports showing a draw on U.S. crude oil inventories, but eased back after EIA data was released.

The price for Brent crude oil Friday was down 1.3 percent to $55.86 per barrel about a half hour before the start of trading in New York. West Texas Intermediate, the U.S. benchmark price for crude oil, was off the previous close by 1.1 percent to $53.87 per barrel.

OPEC's agreement in late November established a floor under crude oil at around $50 per barrel, a price point that was high enough to encourage more spending in U.S. shale oil basins. EIA reported total U.S. production for the week ending Feb. 17 at 9 million barrels per day, with gains even coming from Alaska. Production during the same week in 2016 was 9.1 million bpd. Exports, meanwhile, were reported a 1.2 million bpd, more than double the level from last year.

Strength in U.S. oil has offset OPEC's production efforts so far, keeping oil prices relatively stable. West Texas Intermediate ending last week 43 cents lower than the previous week, but still $23.82 higher year-on-year.

Crude oil prices may be influenced later in the day when oilfield services company Baker Hughes publishes data on exploration and production activity. Gains would indicate a growing appetite for spending in upstream activity. Data on new home sales could factor into broader market activity.