General Kenneth Wilsbach, commander of the US Air Force in the Pacific, said North Korea’s possession of such a weapon was especially unsettling because, unlike other powers, Pyongyang did not consider nuclear arms to be strictly deterrents – kept but never used.
“They’ve threatened to use those weapons against their neighbours, and possibly even the US,” he said. “I mean, if you think about other countries who have those weapons, they don’t talk like that. And so that should have everyone concerned.”
Wilsbach said he “would not be surprised if we saw some sort of test in the near future”, adding that, were one to go ahead, it would “certainly be a game changer” in the region.
“And it would be of great concern to a number of countries,” he added. “I suspect that even China and Russia would be concerned about that.”
Under pressure from international sanctions over its weapons programme, North Korea adopted in September a resolution proclaiming itself an “irreversible” nuclear power.
Pyongyang has carried out six nuclear tests since 2006, with the most recent – and most powerful – in 2017.
Satellite images taken in recent months show signs of activity in a tunnel at the nuclear test site Punggye-ri.