The head of South Korea's spy agency says the U.S. and North Korea’s different priorities in the North's denuclearization process was the reason behind the cancellation of U.S. Secretary of State Mike Pompeo's visit to Pyongyang this week.

That's according to lawmakers who were briefed by National Intelligence Service(NIS) chief Suh Hoon in a closed-door meeting of the National Assembly's Intelligence Committee on Tuesday.

During the meeting, Suh said Pyongyang asked for the adoption of a formal declaration ending the Korean War as a precondition to its denuclearization, while Washington asked Pyongyang to denuclearize first.

When asked how many of the North's assumed 100 nuclear weapons should be destroyed for it to be considered denuclearization, Suh said destroying all of them would be the ultimate goal. In response to a question on whether dismantling 60 of them would be the first phase goal, the intelligence agency chief said "yes."

As for the planned opening of an inter-Korean liaison office in North Korea's Gaeseong Industrial Complex, Suh said the NIS does not consider it a violation of UN sanctions on the North.

[Photo : KBS News]