Investing.com - Oil prices fell on Wednesday after U.S. inventories data showed an unexpected build and a report indicating that OPEC pumped more oil that initially estimated last month, which could offset the effects of a planned production cut.
U.S. crude was trading at $52.29 a barrel at 09:22 GMT, down 69 cents or 1.3% from its last close.
Global benchmark Brent futures were at $55.06 a barrel, falling 66 cents or 1.2%.
Prices were hit after the American Petroleum Institute said late Tuesday that U.S. crude oil inventories rose by 4.7 million barrels last week. Analysts had expected a drawdown of 1.5 million barrels.
Prices came under additional pressure after the International Energy Agency said the Organization of the Petroleum Exporting Countries pumped oil at record levels in November.
OPEC produced 34.2 million barrels a day last month, the IEA said in its closely watched monthly report. This was 500,000 bpd above OPEC's official estimate, which was already a record.
The agency said global oil supply rose to a record 98.2 million bpd in November, as OPEC production offset declines elsewhere.
But the agency also said global oil inventories could swing into a shortfall in the first half of 2017 if producers follow through on the output cut agreement.
The report added to doubts over how effective the planned output cuts will be at rebalancing the market with some analysts skeptical on the ability of major producers to adhere to output limits.
Over the weekend OPEC and non-OPEC producers reached their first deal since 2001 on coordinated production cuts.
Producers from outside OPEC agreed to cut output by 558,000 bpd from January 1, on top of a cut of 1.2 million bpd cut announced by OPEC on November 30.
The total reduction represents almost 2% of global oil output.
Oil production has been outstripping consumption by between one to two million barrels per day since late 2014, pressuring prices lower.