US crude gained four cents to $89.09 a barrel, while Brent North Sea crude rose 27 cents to $114.82.
US crude oil inventories fell by four million barrels last week, according to weekly data published on Thursday by the Department of Energy.
A fall in inventories usually means stronger demand, but analysts said this was not the case last week, attributing the drop instead to a temporary disruption of oil production in the Gulf of Mexico caused by Tropical Storm Lee.
Ongoing worries about the US economy are likely to cap crude prices after data released on Thursday showed new claims for jobless benefits were 414,000 last week, little changed from the previous week.