A deepening feud between Japan and South Korea has threatened to undercut next year's Olympic Games in Tokyo, as the two sides sparred over whether spectators could wave Rising Sun flags associated with Japan's militarist past.

New Olympics minister Seiko Hashimoto — one of the country's best-known Olympians — on Thursday rejected South Korea's call to ban the flag as political propaganda. "On the issue of whether the Rising Sun flag conveys a political message, I don't see it that way at all," she said.

South Korean Culture Minister Park Yang-woo wrote to the International Olympic Committee this week, comparing the flag to the Nazi swastika and pressing for it to be kept out of Olympic venues. The rising sun with rays — distinct from the modern Japanese flag — was used by the Imperial Japanese Army during its invasion and occupation of swaths of Asia.