Top U.S. nuclear envoy Christopher Hill has left for North Korea Monday to discuss North Korea’s nuclear declaration.

During his three-day stay, Hill will examine a five megawatt reactor, a radiochemical laboratory and a fuel rod fabrication plant in Yongbyon.

He will also hold talks with his North Korean counterpart Kim Kye-kwan on the implementation of the October 3rd nuclear accord, under which Pyongyang must dismantle its nuclear facilities in Yongbyon and fully disclose its nuclear program by year's end.