U.S. crude ended the session lower on Tuesday, having fallen as much as 3 percent, weighed down by weaker stocks on Wall Street and skittish sentiment ahead of the expiry of the spot futures contract.
U.S. crude futures' October contract, which expired as the market's front-month at Tuesday's settlement, settled down 85 cents, or 1.8 percent, at $45.83, a barrel. It had risen more than 4 percent on Monday.
The front-month in Brent, the global oil benchmark, turned positive shortly before U.S. crude's settle. It traded up 13 cents at $49.05 by 2:34 p.m. EDT.
The dollar's rise to a nearly two-week high also weighed on oil, as crude and other dollar-denominated commodities became less affordable to users of the euro and other currencies.
Losses in oil were limited though by a Reuters survey showing U.S. crude inventories had fallen almost a million barrels last week, following through with the previous week's decline of 2.1 million barrels.
Traders and investors will get more oil inventory data after market settlement, from industry group the American Petroleum Institute at 4:30 p.m. EDT (2030 GMT). Official stockpile figures are due Wednesday from the U.S. Energy Information Administration.