Cocoa traded in London slipped on Friday amid speculation that demand for the commodity declined and on signs of ample supplies as harvest in West Africa accelerated. Cocoa with delivery in March declined 0.9% to 1,688 pounds, or $2,701, a ton as of 9:56 a.m. on the NYSE Liffe in London, while December cocoa futures fell 1.2% to $2,645 a pound on New York's ICE Futures.