Oil prices fell in early Asian trade on Wednesday after an industry group reported a surprise jump in U.S. stockpiles, fueling concerns about weaker-than-expected demand in the top oil consuming nation.
Brent crude oil futures fell 19 cents, or 0.2%, to $84.82 a barrel by 0023 GMT. U.S. West Texas Intermediate crude futures fell 11 cents, or 0.1%, to $80.72 per barrel.
The American Petroleum Institute (API) reported U.S. crude oil stocks rose by 914,000 barrels in the week ended June 21, according to market sources briefed on the data. Analysts polled by Reuters expect crude stocks to have declined by nearly 3 million barrels last week.
Official U.S. government data on oil and fuel stockpiles is due at 1430 GMT.
Concerns around a weak start to the U.S. summer driving season were partly responsible for a slump in oil prices in the previous session. API reported a 3.84 million barrel jump in U.S. gasoline stocks last week, the sources said, compared with analysts' expectation of a 1 million barrel decline.
Easing U.S. consumer confidence this month added to worries about the economic outlook, and a rising U.S. dollar weighed on oil and other commodities after hawkish comments from Federal Reserve officials, ANZ Bank analysts said.
The U.S. dollar index extended gains slightly on Wednesday after advancing about 0.1% against a basket of currencies in the previous session.
A stronger dollar makes dollar-denominated oil more expensive for investors holding other currencies.