South Korea Navigates the Moscow-Pyongyang Axis Amid Domestic Constraints

The revival of the alliance between Moscow and Pyongyang is prompting Seoul to reconsider its post-Cold War conceptualisation of Russia. Moscow’s diplomatic support has proven critical in sheltering the otherwise faltering Pyongyang and its illicit nuclear and missile programmes. Notably, Moscow has vetoed UN Security Council efforts to impose additional sanctions on the North and to preserve the Panel of Experts overseeing sanctions implementation. Pyongyang’s increasing engagement with BRICS also presents the regime with an opportunity to break out of isolation.

It remains uncertain yet what material support Moscow has provided to the North, but Kim Jong Un is eager to make Putin indebted to him before the war in Ukraine ends, at which point Pyongyang may become more of a liability than an asset to Moscow. According to South Korean intelligence, Pyongyang has already supplied Russia with around eight million artillery shells and short-range ballistic missiles since 2023, estimated to be valued at up to $5.5 billion, or even by the most conservative estimate, $1.7 billion, a significant sum for an impoverished economy with an estimated GDP of $29 billion. The deployment of North Korean troops to Ukraine will undoubtedly raise Pyongyang’s expectations for a reward even higher.

Relations between the two desperately isolated regimes are likely to strengthen for a while. Shortly after news broke of North Korea sending troops to Ukraine, North Korean Foreign Minister Choe Son-hui visited Moscow. This was the third time in 2024 that Choe had met her counterpart, Sergei Lavrov. On this occasion, they reaffirmed their commitment to fully implementing the revived alliance treaty recently ratified in October, aligning with the deployment of North Korean troops. They even commemorated their historical ties dating back to the era of Kim Il-sung, North Korea’s founding father. 

This reinforced commitment, combined with the deployment of North Korean troops, raises multiple concerns for Seoul. First, sending troops could be seen as setting a precedent for putting the mutual assistance clause into action, demonstrating each regime’s willingness to provide military support to the other. This raises the need to factor in Russia in contingency planning, affecting the military balance on the Korean Peninsula and in surrounding regions. The possibility of Russian support could also embolden Pyongyang’s military provocations, further undermining regional stability. Second, while Moscow may hesitate to return the favour due to the relative irreversibility of technology transfers compared to the provision of food or energy, the deployment of North Korean troops to Ukraine strengthens Pyongyang’s leverage in negotiating for rewards, including the potential transfer of nuclear and ballistic missile technologies, a ‘red line’ for Seoul. Third, if North Korean forces gain significant combat experience and data on the performance of their weapon systems, this could contribute to enhancing North Korea’s overall combat capabilities.

Seoul’s Foreign Policy Challenge

The incumbent Yoon administration’s assessment is largely in line with the observations above, which also appear to constitute a broad consensus among experts in Seoul. Immediately following the disclosure by South Korea's National Intelligence Service (NIS) that North Korea had decided to send its troops to Ukraine on 18 October, the South Korean National Security Council defined the situation as a grave security concern. On 21 October, President Yoon held a phone call with the NATO Secretary-General to discuss the situation in Ukraine, and a high-level delegation led by the First Deputy Director of the NIS visited Brussels on 28 October for further discussions. These swift responses were closely followed by high-level communications and meetings with the US, the UK, Japan, Canada, Poland and Ukraine.

Remarks from senior South Korean officials shed light on Seoul’s bottom line, which is to ‘take corresponding measures in line with developments in Russia-North Korea military cooperation (....) in close coordination with allies and partners’. According to the South Korean defence minister, ‘assistance [to Ukraine] will be provided step by step within possible ranges (...) “step by step” means according to the situation in Ukraine and in coalition with the international community (...)’. He has also clarified on multiple occasions that while sending monitoring or analysis teams to Ukraine is necessary, Seoul is not considering sending troops at all.

The Yoon administration has centred its diplomatic vision on the concept of the Global Pivotal State – a commitment to upholding the rules-based order and universal values – but Seoul’s response to the evolving situation will be significantly constrained by domestic politics. The clear stance of ‘no troops’ combined with a cautious, incremental ‘step-by-step’ approach is an illustration of such constraints.

A recent poll indicates that 74.2% of South Koreans oppose providing lethal weapons to Ukraine, while only 20.5% are in favour. Any suggestion of a more significant military commitment could deal a critical blow to the incumbent administration, which is languishing at a 20% approval rating. 

The opposition parties are voicing strong criticism, arguing that the idea of sending a monitoring team, let alone troops, could be a disguised attempt to circumvent the legal requirement for National Assembly approval to deploy troops. There are also concerns that providing weapons to Ukraine would be equivalent to joining the war. Some point to the potential contravention of domestic laws and regulations on military readiness, such as the requirement to maintain an ammunition stockpile sufficient for at least 60 days. Earlier in June, even more fundamental criticisms were made suggesting that the Yoon administration’s value-driven diplomacy was a critical failure, and calling for a shift toward more ‘pragmatic diplomacy'. 

Conclusion

These domestic dynamics will continue to weigh heavily on Seoul’s response. Despite ongoing debates, however, the general consensus is that Seoul is highly unlikely to send troops. Given the administration’s position of taking a ‘step-by-step’ approach and domestic pressures, more defensive assets, such as the Cheongung anti-air interception system, would likely be considered first if Seoul decides to provide any weapons to Ukraine. The possibility of providing offensive weapons such as howitzers, main battle tanks or multiple launch rocket systems is low, particularly for now, as it could limit Seoul’s future options, give Moscow and Pyongyang further justification for their cooperation, and intensify domestic criticism. In the end, a coordinated effort among like-minded partners to establish a common level of commitment will help guide Seoul in navigating the delicate balance between its global vision and domestic constraints.

© Sang Hun Seok, 2024, published by RUSI with permission of the author

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