Cotton futures fell the most in two weeks on speculation that producers are making sales to lock in prices before the U.S harvest boosts supplies.

Yesterday, Cotlook Ltd., the publisher of a benchmark cotton index, boosted its estimate for the global fiber surplus in the year that started Aug. 1 by 55 percent, citing a slump in demand by China , the worldΆs biggest consumer. Earlier this week, futures reached the highest in almost three months.

“Producers are trying to take advantage of the relative high prices,” John Flanagan , the president of Flanagan Trading Corp. in Fuquay-Varina, North Carolina , said in a telephone interview. “The surplus is going to be a big one.”

Cotton for December delivery dropped 2.1 percent to settle at 75.21 cents a pound at 2:32 p.m. on ICE Futures U.S. in New York, the biggest decline since Aug. 10. This week, the most- active contract rose 2.6 percent.