Speaking at a media briefing in Tokyo on Thursday, Iwaya voiced deep concerns about reports from South Korea, the United States, and Ukraine that Pyongyang has sent military personnel to assist Russian forces.
"If North Korea joins in the fighting, the situation in Ukraine will only worsen, further destabilizing the international community," he said.
The diplomatic warning comes amid growing concerns that North Korea could acquire advanced military technology from Moscow in exchange for its support, according to security analysts familiar with the matter.