Kim Jong-un, the senior Kim Jong-il's youngest son, is seen as the leader-in-waiting after he was appointed to senior political and military posts in 2010. Following are analyst views: VICTOR CHA, KOREA EXPERT, CENTER FOR STRATEGIC AND INTERNATIONAL STUDIES, WASHINGTON: "Up until tonight, if anybody had asked you what would be the most likely scenario under which the North Korean regime could collapse, the answer would be the sudden death of Kim Jong-il. "And so I think right now we're in that scenario and we don't know how it's going to turn out. But I think we're definitely in it now." "I think the US and Korean militaries have talked about these sorts of contingencies and scenarios and planned for them. So I think the militaries will start to implement whatever plans they have as precautionary measures to maintain security and stability. "But the real question will be the extent to which the US and ROK will be able to communicate with China. Because these are the three key players when it comes to instability in North Korea. And the Chinese have been reluctant to have any conversations on this. "Now the situation really calls for it. It will be interesting to see how much the Chinese will be willing to have some sort of discussion." ZHU FENG, PROFESSOR OF INTERNATIONAL RELATIONS, PEKING UNIVERSITY, BEIJING: "The speed with which they announced Kim Jong-il's death proves that North Korea's power structure was ready for this and has plans in place. Otherwise, they would have been much slower. This shows the transition mechanisms have already begun working." "The issue of primary concern now is not whether North Korea will maintain political stability, but what will be the nature of the new political leadership, and what policies will it pursue at home and abroad." "In the short-term, there won't be new policies, only a stressing of policy stability and continuity. So soon after Kim Jong-il has died, no leader will dare say that an alternative policy course is needed. The new power structure won't issue new policies in the short term." "The Kim Jong-il era is over, and the post-Kim Jong-il era has begun, and this era will certainly bring change to the Korean peninsula. That's without any doubt. So in these circumstances regional cooperation between China and the United States, as well as Japan, South Korea and Russia, will become all the more important." "No matter what, to speak a bit cruelly, it is a good thing." WEI ZHIJIANG, DIRECTOR OF THE KOREA STUDIES INSTITUTE AT ZHONGSHAN UNIVERSITY, SOUTH CHINA: "The passing of Kim Jong-il won't have any major impact on Chinese-North Korean relations." "Relations won't undergo a big shift because of the passing of one leader." "My assessment is that the ruling apparatus for Kim Jong-un's succession is basically stable. The adjustments to the military, party and government have already been made before Kim Jong-il passed away, and he paved the way for handing over military and party power. To a large degree, Kim Jong-un's rule won't be his individual rule but will involve a bloc." "In economic policy, I think there will be major changes now that Kim Jong-il has passed away, and also in economic opening up there'll also be significant steps." "The generation of Kim Jong-un have a strong awareness that North Korea can't remain isolated from the world."