As recently as 2009, the United States and China reviewed the possibility of a regime failure or other crises in North Korea, the Yonhap News Agency reports.

"When asked on Oct. 4, 2009, whether the United States and China discussed contingencies in North Korea, [then]-Assistant Secretary of State Kurt Campbell acknowledged talks about 'every' aspect," reads a Jan. 3 Congressional Research Service report. No further details were provided about the dialogue.

Any such discussion of crisis scenarios, though, typically would focus in part on securing a nation's most dangerous assets -- in North Korea's case, its nuclear warheads and sensitive atomic materials -- according to issue experts.

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It is not clear if Washington and Beijing have continued talks about contingency scenarios in North Korea, according to the Yonhap report. If such discussions are taking place, they would be delicate and likely kept to avoid inflaming Pyongyang, which already regularly accuses the United States of plotting an invasion.

Following the December purge and execution of Jang Song Thaek -- leader Kim Jong Un's uncle, who had appeared to be the second-most-powerful person in North Korea -- there have been mounting calls for the United States, China and other regional countries to develop specific plans for responding to crises that could emerge from Pyongyang.

Seoul and Washington last week held high-level talks on the importance of preparing for exigencies in the North, which could include armed provocations or fresh attempts to test-detonate nuclear warheads.

Beijing is welcome to join the two allies in planning responses to North Korean contingencies, according to an unidentified high-ranking South Korean official.

The RAND Corp. in a September analysis recommended that China and the United States reach a prior understanding on respective spheres of interest that could be controlled following a possible regime failure in the North, in order to prevent misunderstandings.