West Texas Intermediate crude fell for a second day on speculation that U.S. supplies rose last week. Brent slipped.

WTI dropped as much as 0.7 percent. U.S. crude inventories may have increased 500,000 barrels to near the highest level for this time of year, according to a Bloomberg survey of 10 analysts before a government report tomorrow. Stockpiles at Cushing, Oklahoma, may have climbed from a five-year low, two of the analysts said.

“When you step back and consider the fundamental picture, we still have a lot of supplies,” said Gene McGillian, an analyst and broker at Tradition Energy in Stamford, Connecticut. “If we don’t continue to see tightening fundamentals, at these kinds of levels the market really has a hard time to attract new investment.”

WTI for July delivery slid 54 cents, or 0.5 percent, to $103.57 a barrel at 9:49 a.m. on the New York Mercantile Exchange. The volume of all futures was 26 percent below the 100-day average for the time of day.

Brent for July settlement fell 49 cents, or 0.5 percent, to $109.53 a barrel on the London-based ICE Futures Europe exchange. The volume of all futures was about 28 percent below the 100-day average. WTI was at a discount of $5.96 to Brent. The spread closed at $5.91 yesterday, the narrowest in six weeks.