High-ranking North Korean party and military official Choe Ryong Hae, center left, shakes hands with Chinese Ambassador Liu Hongcai as Choe departs for China as a special envoy of North Korean leader Kim Jong-un, at Pyongyang airport, North Korea Wednesday, May 22, 2013. (AP Photo/ Kim Kwang Hyon)

Photo by: Kim Kwang Hyon

High-ranking North Korean party and military official Choe Ryong Hae, center left, shakes hands with Chinese Ambassador Liu Hongcai as Choe departs for China as a special envoy of North Korean leader Kim Jong-un, at Pyongyang airport, North Korea Wednesday, May 22, 2013. (AP Photo/ Kim Kwang Hyon)