The United States declined comment on U.N. Secretary-General Ban Ki-moon's plan to visit North Korea this week, saying it has no related information.

A State Department official also said that related queries should be referred to the U.N.

Earlier in the day, a high-level diplomatic source at the United Nations told Yonhap News Agency that Ban plans to visit Pyongyang later this week. It will be Ban's first visit to the North since taking office as U.N. chief in early 2007.

He will also be the third U.N. secretary-general to visit North Korea after Kurt Waldheim in 1979 and Boutros Boutros-Ghali in 1993. Both Waldheim and Boutros-Ghali met with North Korea's founding leader Kim Il-sung during their visits to Pyongyang.

Ban is also expected to meet with North Korean leader Kim Jong-un. (Yonhap)