Crude-oil futures added to losses Wednesday after a weekly government report showed a surprise increase in inventories.
Crude for September delivery declined 90 cents, or 1.1%, to $87.56 U.S. a barrel on the New York Mercantile Exchange.
It had traded at $88.40 U.S. a barrel moments before the report.
The Energy Information Administration said crude supplies rose 2.7 million on the week ended July 20. That contrasted with expectations of a decline around 250,000 barrels, according to analysts polled by Platts.
The EIA also reported gasoline stockpiles up 4.1 million barrels, and inventories of distillates up 1.7 million barrels. The analysts surveyed by Platts had expected gasoline inventories down 750,000 barrels and distillates supplies up one million barrels
