KEY TAKEAWAYS
KEY TAKEAWAYS
The Ukraine war is taking a new turn with the involvement of North Korean soldiers. Washington estimates that, so far, North Korea has sent approximately 10,000 troops to Russia — around 8,000 of whom have been deployed to the western region of Kursk, where Ukraine seized territory in a surprise attack earlier this year. And as U.S. officials predicted in late October, North Korean troops have reportedly begun engaging in direct combat.
Ukrainian President Volodymyr Zelensky rightfully lamented that these “first battles with North Korea open a new chapter of instability in the world.” The global consequences cannot be understated, as this development raises serious concerns not just for the war in Ukraine, but for security on the Korean Peninsula as well.
For the first time since the Korean War in the 1950s, the North Korean military is gaining large-scale combat experience. Although North Korea previously sent small contingents to conflicts such as the Vietnam War, the 1973 Yom Kippur War and reportedly the Syrian Civil War in recent years, it hasn’t been involved in a large-scale war in over seven decades.
But now, North Korean soldiers in Ukraine will witness modern warfare, including the use of advanced weaponry such as drones, and those who return will contribute to North Korea's military planning and preparations.
Additionally, North Korea stands to gain critical hard currency, long denied due to economic sanctions. According to South Korea’s intelligence agency, Russia is expected to pay $2,000 per soldier per month, totaling $20 million each month. These cash flows could strengthen North Korea’s economic flexibility, allowing it to allocate funds toward enhancing its military capabilities.
The greatest threat to South Korea, however, is the possibility that Russia might provide North Korea with advanced military technologies.
The greatest threat to South Korea, however, is the possibility that Russia might provide North Korea with advanced military technologies such as: re-entry vehicle technology to enhance its missile capabilities; nuclear-powered submarine technology to enhance its second-strike capacity; high-resolution satellite imaging for improved intelligence, surveillance and reconnaissance capabilities; and combat aircraft to reduce the gap with South Korea’s air superiority.
These technologies could shift the inter-Korean military balance by significantly enhancing North Korea’s nuclear and missile capabilities while diminishing South Korea’s edge in conventional forces.
In response to the escalating military cooperation between Russia and North Korea, South Korean President Yoon Suk-yeol stated that Seoul “won’t sit idle” and is prepared to take countermeasures, including the potential direct supply of weapons to Ukraine.
So far, South Korea has provided Ukraine with humanitarian assistance and non-lethal military supplies, including protective gear, medical supplies, demining vehicles and financial contributions totaling $394 million so far this year. Although South Korea has indirectly supplied Ukraine with 155-mm artillery shells through the United States — providing more of these shells last year than all European countries combined — it has refrained from directly supplying lethal arms to Ukraine.
Yoon said Seoul could reverse this policy in response to North Korea’s involvement. Similarly, a senior official in Yoon’s office said: “We would consider supplying weapons for defensive purposes as part of the step-by-step scenarios, and if it seems they are going too far, we might also consider offensive use.”
Yoon confirmed this position on November 7 by saying “depending on the level of North Korean involvement, we will gradually adjust our support strategy in phases … This means we are not ruling out the possibility of providing weapons.”
However, this action poses several problems. To begin with, directly providing weapons to Ukraine would violate South Korea’s Foreign Trade Act, which stipulates “strategic materials shall only be licensed if they are used for peaceful purposes.”
President Yoon does not have the authority to unilaterally make this change. Revising the law to allow for providing weapons to Ukraine would require National Assembly support — a difficult task given that the Assembly is dominated by South Korea’s Democratic Party, which has been critical of arms supplies to Ukraine.
Additionally, public opinion is overwhelmingly against such a move. In a recent poll, only 13 percent supported supplying arms to Ukraine, while 82 percent opposed it. If anything, this may become even harder, as South Korea’s Democratic Party has proposed a bill requiring prior National Assembly approval before lending or transferring lethal weapons to countries engaged in international conflicts.
Furthermore, this action might not be seen as a proportional response to Russia’s actions. Russia’s invitation to North Korean soldiers is an escalation with potential secondary and tertiary effects on South Korea — but it does not directly target South Korean lives. Meanwhile, supplying Ukraine with lethal weapons that could kill Russians on Russian territory would represent a significant escalation beyond Russia’s actions. It might prove unwise for Seoul to advance several rungs on the escalation ladder.
Most importantly, Seoul’s ultimate objective in providing weapons remains unclear. If deterrence is the aim, then critical questions arise: Who are they trying to deter — North Korea or Russia? And what specific actions are they seeking to deter?
What should South Korea’s goals be? It’s presumably too late to secure the withdrawal of North Korean troops from Russia or to prevent North Korean soldiers from participating in combat, as coercing someone to reverse an action is much harder than deterring them from taking further steps.
Instead, South Korea can establish an effective red line on Russia providing North Korea with sensitive technologies that could significantly enhance its military capabilities. While verifying Russia's restraint in this capacity may be challenging, South Korea should insist on a formal commitment from Russia to abstain from such actions.
To this end, Seoul can expand upon its current phased approach to outline specific South Korean responses that will correspond with specific Russian escalations and actions going forward.
The first step could be to increase its non-combat aid, focusing on types that go a step beyond the humanitarian and non-lethal support currently being provided. This could mean providing Ukraine with non-lethal yet strategically important dual-use equipment that has both civilian and military uses, such as sensors, cameras and communication systems that collect data and reliably transmit it to command centers in real time. Seoul could also consider deploying civilian personnel to assist Ukraine in interrogating North Korean prisoners of war to gather military intelligence.
Simultaneously, Seoul should communicate with Russia, insisting that any compensation to North Korea should not be in the form of military support. Should Russia refuse to comply, South Korea could gradually escalate its response by indirectly supplying Ukraine with defensive weapons through other partners of Ukraine.
After two-and-a-half years of support, Ukraine’s arms suppliers have significantly depleted their defense stockpiles, making it increasingly difficult to sustain aid. For example, the U.K.’s military reserves have become so “threadbare” that they now pose “unacceptable risks to the U.K.’s military readiness,” prompting a sharp reduction in arms supplies to Ukraine last year.
Meanwhile, U.S. defense stockpiles have also been strained by its support for Ukraine, Israel and Taiwan — with reports indicating that U.S. reserves for air defense systems, specifically, are rapidly dwindling.
South Korea could consider supplying weapons to these and other third parties to replenish their stockpiles, facilitating ongoing support for Ukraine's defense needs. It could start by providing air defense systems, which are less escalatory given their defensive purpose and align with Ukraine's most urgent requirements. These could include the Hawk surface-to-air missile defense systems and more advanced systems like the Cheongung II, South Korea’s equivalent of the U.S. Patriot III.
A further step could involve indirectly supplying more offensive weapons, such as armored vehicles (notably tanks and self-propelled howitzers), which have been recognized for their advanced technology, reliability and battlefield effectiveness. Although South Korea already supplies weapons to European countries, particularly Poland, the primary purpose has been to bolster their defense capabilities rather than indirectly support Ukraine (apart from providing ammunition to the United States). Seoul could more explicitly align its arms sales to the West with an intent to support backfill efforts for Ukraine.
Seoul could more explicitly align its arms sales to the West with an intent to support backfill efforts for Ukraine.
If South Korea’s indirect supply of weaponry fails to force Russia to agree to South Korea’s demands regarding sensitive technology transfers to North Korea, Seoul could eventually consider delivering weapons directly to Ukraine, pending consultation with the National Assembly.
Despite Yoon's low popularity and the opposition-controlled Assembly, there’s still a way that a consensus on direct weapons deliveries to Ukraine could be reached. Opposition to Yoon’s direct weapon deliveries is not only driven by the associated risks, but also by concerns over bypassing legal procedures. A proper consultation between the Yoon administration and the National Assembly that frames the move as a deterrent to Russian actions that pose a significant threat to South Korea’s national security — and emphasizes the strength of a unified stance — might make the Assembly more receptive to direct arms supplies to Ukraine.
The possibility of South Korean arms supply to Ukraine — whether direct or indirect, though especially in the case of direct support — could impose significant costs on Russia, potentially strengthening South Korea’s bargaining position with Moscow.
South Korea can provide precisely the types of arms that Ukraine urgently needs to sustain its resistance, and its robust defense industrial base would ensure a steady and rapid supply of these arms. Although Russia currently outproduces the West in weaponry, South Korea could potentially shift this defense production balance, undermining Russia’s goal of pressuring Kyiv into peace negotiations.
The Yoon administration’s initial response to North Korean’s involvement in Ukraine risks appearing unnecessarily escalatory. However, given the potentially dangerous repercussions of military cooperation between Russia and North Korea, ignoring this development is not a wise option either. South Korea should aim to strike a delicate balance. A phased approach, as outlined above, incorporating a clear message and explicit penalties, would provide South Korea with better leverage to deter Russia from supplying North Korea with military capabilities that pose an existential threat.
Lami Kim is a professor at the Daniel K. Inouye Asia-Pacific Center for Security Studies, a U.S. Department of Defense institute based in Hawaii. The views expressed are those of the author and do not necessarily reflect the official policy or position of the U.S. Department of Defense or the U.S. government.