U.S. retailers including Toys R Us are starting to negotiate with their Chinese suppliers to take advantage of lower manufacturing costs after China devalued the yuan, with many saying they want to be ready if currencies in China and other Asian countries drop more against the dollar. Earlier this month, China devalued its tightly controlled currency in an effort to boost growth and help flagging exports. The nearly 2 percent cut on Aug. 11, the most significant downward adjustment to the yuan since 1994, will make imports from China cheaper.