Japan's largest clothing maker Fast Retailing Co. issued an apology on its Korean website for remarks that angered Korean customers amid the trade spat between Japan and South Korea.

At its earnings news conference on July 11, the Uniqlo owner's chief financial officer Takeshi Okazaki said he "thinks" that the impact of a boycott of Japanese goods wouldn't last long.

In its statement, Fast Retailing clarified that the remarks were intended to mean that the company "hoped" the impact wouldn't be long-lasting, and apologized for upsetting Korean customers.

The remarks were "insufficient," it said, and unintentionally conveyed the impression that the company expected the boycott movement wouldn't last long. It also posted the remarks on its Japanese website.

Credit-card purchases at Uniqlo stores in South Korea dropped 26 percent recently, according to an analysis by a credit card company cited by the JoongAng Ilbo newspaper.