Oil gave up short-lived gains following mixed U.S. government data that showed a bigger-than-expected build in crude stockpiles, rising gasoline demand, and falling oil production.
Brent crude was down 61 cents at $44.08 U.S. a barrel , having briefly risen to a new 2016 high of $44.94 following the release of the figures from the Energy Information Agency.
U.S. crude was settled down 41 cents, or nearly 1%, at $41.76 U.S., after also rising to a 2016 high of $42.42 U.S.
The EIA reported U.S. crude inventories increased by 6.6 million barrels, bringing the total in storage to 536.5 million barrels in the previous week.
But a larger-than-expected draw in gasoline inventories softened the blow of soaring crude stocks. Gasoline fell by 4.2 million barrels to 239.76 million, compared with an analyst forecast of a 1.4-million-barrel draw.
Production numbers in the United States also declined below nine million barrels per day for the first time since late 2014 in a sign that the consistent decline in rig counts is having an impact on output, analysts said.
Prices had been lower on Wednesday on concerns that a producer meeting on Sunday to discuss freezing output will do little to trim oversupply.
The Organization of the Petroleum Exporting Countries lowered its forecast of world oil demand growth by 50,000 barrels per day (bpd) and said in its monthly report on Wednesday further downward revisions could follow.
OPEC pumped 32.25 million bpd in March, up about 15,000 bpd from February.
