Oil prices fell on Tuesday, pressured by sluggish demand and evidence of a burgeoning revival in U.S. shale production that could complicate efforts by OPEC and other producers to reduce a supply glut.
Benchmark Brent crude was down 80 cents at $54.92 a barrel by 11:31 EST (1531 GMT). On Monday, the Brent futures contract closed down $1.09 a barrel. U.S. crude was 96 cents lower at $52.05 after closing down 82 cents on Monday.
Gasoline futures fell 2.66 cents or 1.77 percent to $1.4837 a gallon.
"It's a supply-driven setback ... We are within 2 million barrels of the record in U.S. gasoline stocks that we saw last February," said Tony Headrick, energy markets analyst at CHS Hedging. "A strong build in inventory reports could weigh on gasoline in a seasonal timeframe where gasoline demand is weak."
Inventory estimates from trade group the American Petroleum Institute are due on Tuesday afternoon. U.S. government data is reported Wednesday.
Gasoline futures fell below the 200 day moving average on a continuous chart, Headrick noted, adding that if they close below that level, it could further pressure crude.
Prices have been supported for two months as the Organization of the Petroleum Exporting Countries and other exporters have tried to cut output by almost 1.8 million barrels per day (bpd) in the first half of 2017. OPEC and Russia have together cut at least 1.1 million bpd so far.
But market players are concerned that rising U.S. production and signs of slowing demand growth could offset these efforts.
"The general perception is that OPEC is cutting production, which is supporting prices, but high stock levels, rising rig counts and growing U.S. production are capping gains," said Tamas Varga, analyst at London brokerage PVM Oil Associates.
Societe Generale oil analyst Michael Wittner said U.S. shale oil output was recovering faster than expected.
"Rig counts are increasing at an accelerating pace, and given the technological advances of the past three years, this should translate into significant supply," Wittner said.
"U.S. shale is coming back, and it's coming back strong."
Chinese oil demand grew in 2016 at the slowest pace in at least three years, Reuters calculations showed, the latest sign of slower demand from the world's largest energy consumer.
Some think U.S. gasoline demand is stalling.
Gasoline stockpiles rose by almost 21 million barrels in the first 27 days of 2017, more than double the average increase of less than 12 million barrels at the same time of year during the previous decade, official inventory data showed.
(Additional reporting by Christopher Johnson in London and Henning Gloystein in Singapore; Editing by Dale Hudson and Jason Neely)