Two North Korean officials have canceled a scheduled visit to the South for a peace conference.
Local officials in Gyeonggi province say the North Korean side cited "unavoidable" circumstances.
One of the North Koreans, Kim Song-hye, is a key official in inter-Korean affairs and negotiations with the U.S..
She had been expected to meet with South Korean officials to discuss inter-Korean relations and other issues during her visit.
Kim accompanied the North Korean leader's sister Kim Yo-jong to South Korea this year, and joined Workers' Party Vice Chairman Kim Yong-chol on a visit to the U.S. in May.