North Korean leader Kim Jong Un appears to be considering "Plan B" for future nuclear negotiations amid a months-long diplomatic impasse, former ROK Permanent Representative to the UN Kim Sook said in a recent interview with NK News, warning that the Moon Jae-in administration must be prepared.

"So, I think we have to prepare our own Plan B. I think there are two possibilities for our Plan B," Kim said, adding that these two Plan Bs would be "polar opposites."