Fast Retailing Co., operator of the Uniqlo chain of casual clothing, raised its profit forecast by 18 percent on overseas growth and lower costs even as other retailers say the March 11 disaster will hurt earnings.

Net income may total ¥60 billion ($706 million) in the year ending Aug. 31, more than the earlier estimated ¥51 billion, Fast Retailing said in a statement Thursday. China and South Korea are gearing up to be "big business" for the retailer, company President Tadashi Yanai told reporters in Tokyo.

Japan's retail sales may drop as much as 10 percent this year because of the earthquake and tsunami that left thousands dead and obliterated towns in the Tohoku region, according to convenience store chain FamilyMart Co. While Fast Retailing's March sales were affected by the disaster, sales at stores open more than a year will start rising this month, Nobuo Domae, group executive vice president, said Thursday in Tokyo.