On October 13, 2025, South Korea’s Defense Minister, Ahn Gyu-back, made a striking claim before parliament: North Korea has likely received technical assistance from Russia in its ongoing efforts to develop advanced submarines. This revelation, delivered during a parliamentary Defense Committee hearing, comes amid a period of rapidly intensifying military cooperation between Pyongyang and Moscow, raising alarm bells in Seoul and beyond about the shifting security dynamics in Northeast Asia.
Minister Ahn’s testimony, as reported by Reuters and other major outlets, underscored the seriousness of the situation. He stated, “It appears true that the North was receiving various technologies for its submarine development.” According to South Korean intelligence assessments cited by Ahn, North Korea’s push for submarine capabilities has been bolstered by Russian expertise, though the full extent and specifics of this support remain closely guarded secrets.
For years, North Korea has openly declared its ambition to develop submarines capable of launching ballistic missiles—a technological leap that would significantly enhance its second-strike capability and complicate regional defense calculations. Pyongyang has already test-fired ballistic missiles from submerged platforms, but, as Ahn pointed out, it remains unclear whether the North has truly mastered the highly complex feat of launching such missiles from an operational submarine.
“It is premature to conclude Pyongyang had test-launched a submarine-launched ballistic missile (SLBM) from a submarine,” Ahn cautioned, tempering speculation about North Korea’s progress. He stressed that while North Korea has demonstrated some capabilities, the evidence does not yet support claims of a fully functional SLBM system launched from an actual submarine. This distinction is crucial: launching from a submerged platform is one thing, but executing a launch from a moving submarine, undetected, would mark a major technological milestone.
Nevertheless, North Korea’s ambitions do not stop at conventional submarines. According to the reports, Pyongyang is also pursuing the development of nuclear-powered submarines, a move that, if successful, would represent a dramatic escalation in its naval prowess. Nuclear-powered submarines can remain submerged for months, travel vast distances, and are far harder to detect than their diesel-electric counterparts. Such capabilities would allow North Korea to project power far beyond its shores and potentially threaten targets across the region and even further afield.
The backdrop to these developments is a deepening military partnership between North Korea and Russia, which has grown significantly over the past two years. South Korean intelligence sources, as cited by Reuters and corroborated in multiple reports, allege that Pyongyang has deployed more than 10,000 troops to fight in the ongoing war against Ukraine. In return, North Korea is believed to have received not only economic support but also critical military technology—including, it appears, the very submarine know-how now under scrutiny.
This arrangement has raised eyebrows among security analysts and policymakers. The deployment of North Korean troops to Ukraine marks a rare instance of Pyongyang directly involving itself in a foreign conflict on this scale, and the quid pro quo—military and economic aid from Russia—has emboldened North Korea’s own weapons programs. The details of this cooperation remain murky, but the implications are clear: two of the world’s most isolated and heavily sanctioned states are finding common cause, with potentially destabilizing consequences for the region.
For South Korea, the prospect of a more capable North Korean navy, equipped with advanced submarines and possibly even nuclear-powered vessels, is deeply concerning. Submarine-launched ballistic missiles would provide North Korea with a survivable nuclear deterrent, able to evade preemptive strikes and retaliate against adversaries even after a first blow. This would complicate any military planning by Seoul and its allies, including the United States, and could trigger a regional arms race as neighboring countries seek to counter the new threat.
Yet, as Minister Ahn emphasized, there is still a gap between North Korea’s aspirations and its actual capabilities. The technical hurdles involved in developing operational SLBMs and nuclear submarines are formidable. Building a reliable launch system that works from a submerged, moving platform requires advanced engineering, robust testing, and extensive resources—areas where North Korea has historically struggled due to sanctions and limited industrial capacity. That’s where Russian assistance could prove decisive, and why South Korean officials are watching developments so closely.
The broader context is equally important. The North Korea-Russia partnership is not occurring in a vacuum. Both countries have faced increasing isolation from the West—North Korea due to its nuclear weapons program and human rights abuses, and Russia because of its invasion of Ukraine and the resulting international sanctions. Their collaboration represents a convergence of interests: Russia gains manpower and perhaps munitions for its war effort, while North Korea secures technology and economic support to advance its own military agenda.
Observers note that this relationship is reminiscent of Cold War-era alliances, where ideological and strategic interests often trumped concerns about international norms or regional stability. Now, as then, the rest of the world is left to grapple with the consequences. For the United States and its allies, the challenge is twofold: deterring North Korean aggression while preventing further proliferation of advanced military technology in the region.
Meanwhile, the North Korean regime appears undeterred by international criticism or sanctions. Its leadership has repeatedly vowed to continue developing its strategic weapons, framing these efforts as essential for national defense and regime survival. The addition of Russian expertise, if confirmed, would only accelerate these programs and raise the stakes for all involved.
As the situation evolves, policymakers in Seoul, Washington, and other capitals will be weighing their options. Enhanced intelligence sharing, increased naval patrols, and new sanctions are all on the table, but the effectiveness of these measures remains to be seen. What is clear is that the security environment in Northeast Asia is growing more complex, with old alliances shifting and new threats emerging.
Minister Ahn’s remarks to parliament serve as a stark reminder that the interplay of technology, military ambition, and international alliances can reshape the strategic landscape in unpredictable ways. For now, all eyes are on Pyongyang and Moscow, as the world waits to see just how far this partnership will go—and what it will mean for peace and stability in the region.
