Earlier this week, the chief nuclear negotiators of South Korea, the U.S. and Japan were united in pressuring North Korea not to carry out a fourth nuclear test.
"It would be a direct provocation to the international community and a grave threat to global peace and stability. We, along with the international community will make sure North Korea pays for it."
The three nations together with China and Russia have tried to denuclearize the North for more than a decade, but each participating country's political interests have gotten in the way.
Behind the three parties' unified voice, Seoul and Washington reportedly demanded Tokyo's transparency in its recently revived two-way dialogue with Pyongyang.
That's because the three allies have maintained that they will not resume dialogue with North Korea unless it takes steps to end its nuclear program and that bilateral arrangements with North Korea must not undermine this principle.
The Abe administration, however, recently opened government-level contacts with Pyongyang, seeking explanations about North Korea's abductions of Japanese nationals during the 1970s and 80s.
Any progress on North Korea's nuclear issue requires cooperation from its traditional ally China, which wants unconditional dialogue resumption with Pyongyang.
But the U.S. and China appear to be more obsessed with military rivalry in the Asia-Pacific region.
The two global powers have recently been engaged in a war of words over China's territorial claims in the region.
With cracks surfacing in relations among nations involved in containing North Korea's nuclear ambition, priority may well be burying their differences.
Choi You-sun, Arirang News.