Brent crude rebounded from a one-month trough on Wednesday while U.S. crude closed at its lowest since February after oil inventories in the United States hit record highs.
The U.S. Energy Information Administration said U.S. crude stockpiles rose by 4.5 million barrels last week, trumping some traders' expectations after an industry report on Tuesday posted a slight drop instead. Inventories have written new records for nine weeks now, standing at nearly 490 million barrels.
"We have to go back to the 1930s to find this much oil in the United States," said James L. Williams, energy economist at WTRG Economics in London, Arkansas.
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Last week's increase included a 2.3-million-barrel build at the Cushing, Oklahoma delivery point of the U.S. crude contract. Genscape, a market data provider, had indicated earlier this week that Cushing saw a build of just around 157,000 million barrels last week.