Oil fell back on Thursday as disappointing U.S. economic data and renewed euro-zone debt worries stoked fresh oil demand concerns.

Oil's decline after Wednesday's 2 percent gain on tighter U.S. distillate inventories dragged the 19-commodity Reuters-Jefferies CRB index <.CRB> 0.4 percent lower.

The latest U.S. growth estimate for the first quarter showed an unrevised 1.8 percent rise, but that was below expectations, and corporate profits unexpectedly shrank while weekly jobless benefit claims rose.

Today's U.S. first quarter GDP estimate is disappointing and the job claims numbers were soft, said Bill O'Grady, chief market strategist at Confluence Investment Management in St. Louis, Missouri.

U.S. crude for July delivery fell $1.40 to $99.92 by 11:40 a.m. EDT (1540 GMT).

In London, ICE July Brent crude dropped 55 cents to $114.38.

Brent's losses were limited by a weaker dollar and concerns about the Middle East and North Africa.

(Additional reporting by Simon Falush in London, Francis Kan in Singapore; Editing by Marguerita Choy)