West Texas Intermediate fell on speculation that U.S. inventories increased for an 11th week, and as a gauge of U.S. manufacturing rose less than expected. Brent slipped.

WTI dropped as much as 1 percent. Stockpiles may have climbed 2.5 million barrels last week, according to a Bloomberg survey before a government report scheduled for release tomorrow. The Institute for Supply Management’s index reached 53.7 in March, lower than the 54 forecast in a Bloomberg survey. A separate report showed weakness in Chinese manufacturing.

“All the news is bearish today,” said Michael Lynch, president of Strategic Energy & Economic Research in Winchester, Massachusetts. “The manufacturing data is not supportive and we are expecting another build in inventories.”

WTI for May delivery declined 87 cents, or 0.9 percent, to $100.71 a barrel at 10:12 a.m. on the New York Mercantile Exchange. The volume of all futures traded was 18 percent below the 100-day average. Prices dropped 1 percent in March.

Brent crude for May settlement slid 60 cents, or 0.6 percent, to $107.16 a barrel on the London-based ICE Futures Europe exchange. Volume was 25 percent below the 100-day average. The European benchmark was at a $6.45 premium to WTI after closing at $6.18 yesterday.