Oil fell on Tuesday, hitting one-month lows, as U.S. gasoline prices pared an early rally sparked by a pipeline blast and crude was also pressured by renewed doubts about whether OPEC will follow through with proposed output cuts.
The American Petroleum Institute (API) reported U.S. crude stocks rose by 9.3 million barrels in the last week. Analysts had forecast that U.S. crude stocks had increased by more than 1 million barrels last week after unseasonal declines in seven of the past eight weeks also weighed on crude.
The API report came ahead of official government data on Wednesday.
U.S. West Texas Intermediate (WTI) futures settled down 19 cents, or 0.4 percent, at $46.67 a barrel, after a near-4 percent drop on Monday. They were lower after the settle following the API release.
Brent January crude futures were down 64 cents, or 1.3 percent, at $47.97 a barrel by 4:50 p.m. ET (2050 GMT). They fell by nearly 3 percent the day before in their biggest one-day drop since Sept. 23.
Crude was up earlier, boosted as the U.S. dollar slid, making dollar-denominated oil cheaper for users of other currencies.
Crude was also helped by a gasoline rally after Colonial Pipeline Co shut its main gasoline and distillates pipelines following an explosion in Alabama. Gasoline futures jumped 13 percent, then pared gains on news Colonial had reopened another gasoline line.
"Oil rode up at first on the Colonial pipeline news, but that effect has faded," said John Kilduff, partner at New York energy hedge fund Again Capital.
"All attention is back on OPEC's failure thus far to put together a convincing production cut plan, and the possibility of higher U.S. crude stocks from here."
Crude prices rallied about 15 percent over a three-week span after the Organization of the Petroleum Exporting Countries proposed on Sept. 27 its first production cut in eight years to reign in a global oil oversupply. Brent hit one-year highs and WTI 15-month peaks in early October as OPEC kingpin Saudi Arabia talked up the plan, inviting non-member producers such as Russia to make cuts too.
In the past two weeks, however, a growing number of OPEC member have said they were unwilling or unable to cut, casting doubts on what the group could do when it meets on Nov. 30 in Vienna.
"Notwithstanding day-to-day rebounds, the oil rally since late September on the notion of OPEC cuts has been almost wiped out," said David Thompson, executive vice-president at Powerhouse, a commodities-focused broker in Washington.
"It looks like we will break down more momentously unless the Saudis intervene with big output cuts of their own," said Thompson, who sees WTI testing support next at $45.
OPEC officials approved on Monday a document outlining the exporter group's long-term strategy, in a sign its members are making progress in ironing out differences over how and when to manage production levels and, ultimately, oil prices.
OPEC has called upon major producers outside of the group to agree to limit output, but with limited success so far. Top oil producer Russia has said it will consider freezing output. Kazakh Energy Minister Kanat Bozumbayev said on Tuesday his country would not cut output, particularly as the Kashagan field ramps up to a target of 200,000 bpd by the end of this year.
"Even if the fear of such low prices leads OPEC to deliver an agreement on November 30, we reiterate our view that the odds of it succeeding are low," Goldman Sachs said in a research note.
Colonial Pipeline shut down its main gasoline and distillates pipelines on Monday after an explosion and fire in Shelby, Alabama, killing a worker and sending five to the hospital — the second time in two months it had to close the crucial supply line to the U.S. East Coast.
The site was about a mile west of a massive leak last month that closed the gasoline pipeline for over 12 days, according to the office of Alabama Governor Robert Bentley.
Colonial said its main gasoline line could be open as early as Saturday. Crews have isolated the fire, which came weeks after its biggest gasoline spill in nearly two decades shut the same line for 12 days, it said.
The pipeline closure drove up gasoline prices at the pump in the U.S. Southeast and on futures markets.
The 5,500-mile (8,850-km) Colonial Pipeline is the largest U.S. refined products pipeline system and transports gasoline, diesel and jet fuel from the U.S. Gulf Coast to the New York Harbor area. The pipelines that shut run from Houston to Greensboro, North Carolina.
— CNBC's Tom DiChristopher contributed to this report.