Expectations of a lower price for Brent crude oil kept keep indices treading water in early Thursday trading, relatively unchanged to start the day.

Brent crude oil prices ended Wednesday at $66.81, down 1 percent for the day. Brent traded Thursday at $66.87, relatively stable for the month. European economy data helped the early Wednesday rally, though suggestions markets were still weighed heavily on the supply side pushed prices down through the trading day.

The U.S. Energy Information Administration in a market report for May said it expected Brent crude oil prices would average around $63 per barrel, a 14.5 percent increase from its April prediction, for the second half of the year.

Stronger global demand, an expected slump in U.S. oil production and continued security concerns in the Middle East and North Africa were in part behind the EIA's revision. EIA, however, lowered its 2016 forecast for Brent by $5, or 6.6 percent, to $70 per barrel.

A Monday report from The Wall Street Journal said the Organization of Petroleum Exporting Countries expect crude oil prices to say below the $100 mark through the middle of the next decade. OPEC later issued a statement saying the report contained "numerous inaccuracies."

Depressed crude oil prices are throttling spending on exploration and production, though North Dakota, a key U.S. shale producer, reported an increase in oil output in its latest monthly report despite a slump in rig activity.

West Texas Intermediate, the U.S. standard, was relatively unchanged from Wednesday close to trade at $60.35 per barrel, up about 2 percent since the start of the month.