U.N. Secretary-General Ban Ki-moon plans to visit North Korea this week, a high-level U.N. source said Sunday, a surprise trip that raises hope for progress in inter-Korean relations and efforts to resolve the North Korean nuclear standoff.

Ban's visit to Pyongyang will be the first time in his capacity as U.N. chief, the source told Yonhap News Agency without providing exact dates of the trip. The source spoke on condition of anonymity because the trip has not been formally announced.

It was also unclear whether Ban asked to make the trip or Pyongyang invited him.

Ban will 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.

"There can't be such a situation where the U.N. secretary-general visits North Korea and does not meet with the supreme leader of the U.N. member state," the source said.

The source said Ban won't be coming back from the trip empty-handed, adding that there is a high possibility that the trip could produce an important opportunity for resolving the North Korean nuclear issue and other Korean Peninsula matters.

In May, Ban planned to visit the North Korean border city of Kaesong, where South Korea runs an industrial complex, but the trip was called off at the last minute because Pyongyang abruptly withdrew its invitation for him for no clear reason.

Some analysts said at the time that Pyongyang appeared to have taken issue with Ban's remarks that North Korea's missile launches represent a violation of U.N. Security Council resolutions.

Ban, a former South Korean foreign minister, has repeatedly said that he will do everything possible to promote inter-Korean reconciliation and a resolution of the North Korean nuclear issue. (Yonhap)