"We cannot question the seriousness of the situation," says Paik Hak Soon, senior researcher on North Korea at South Korea's Sejong Institute. "The UNSC resolution was all-out confrontation, and North Korea is countering in its own way."
Mr. Paik says he has no doubt that North Korea is preparing for its third nuclear test while advancing its uranium enrichment program.
"There is no stopping North Korea's actions," he says.
What's the status on the North's uranium and plutonium?
The UN resolution theoretically calls for cooperation in halting proliferation of the components and technology for fabricating nuclear weapons, but North Korea is assumed to have all it needs to produce more warheads with plutonium at their core at its central nuclear complex at Yongbyon, 60 miles north of Pyongyang.