Fast Retailing Co., operator of the Uniqlo casual clothing chain, said Thursday that President Genichi Tamatsuka will step down Aug. 31 and be replaced by Chairman and CEO Tadashi Yanai.

Tamatsuka, 43, said he will resign after failing to deliver on his pledge of achieving 400 billion yen in sales.

The company also announced sweeping changes to its corporate structure, including the creation of holding company FR Holdings Co. on Nov. 1, under which Uniqlo will become a separate entity along with overseas subsidiaries.