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The past few weeks have been marked by a flurry of footage and intelligence tidbits revealing North Korea’s deployment of its forces to Russia. Initial incredulity on the South Koreans’ part gradually turned into consternation, as clips circulating online showed scrawny North Koreans, uttering undeniably fluent Korean, in Russia.
South Korea’s National Intelligence Service (NIS) confirmed that Russia’s Pacific Fleet and transport aircraft had fetched 1,500 North Korean special forces to training bases in Russia’s Far East. Pyongyang also dispatched some 4,000 laborers to further bolster Russia’s war-making capacity.
They were the first vanguard batch of what has since peaked to around 12,000 North Korean troops, equivalent to four brigades. Most of them are now stationed in Kursk, a Russian region bordering Ukraine’s northeast where claims of first skirmishes between Ukrainian and North Korean combatants have arisen since early November.
We have previously seen small numbers of North Korean agents and soldiers taking part in conflicts around the globe. During the Vietnam War, hundreds of North Korean commandos and pilots fought against the United States. In 1973, North Korea sent 20 pilots to Egypt to back the latter’s operations against Israel. In the 1980s, some 3,000 North Korean soldiers and advisers participated in the Angolan Civil War. More recently, it dabbled in Syria’s civil war with a couple of combat units and missile technicians.
But North Korea’s military involvement in Ukraine and the concomitant escalation are unprecedented and shocking in scale. This came on top of Pyongyang’s shipment of anti-tank missiles, short-range ballistic missiles, rocket-propelled grenades and over 8 million artillery shells to Russia.
Supplying munitions to Russia already violates international law through indirect use of force against Ukraine. If North Korea ventures past its heretofore limited advisory roles and operational support in other countries and engages in combat against Ukraine – as opposed to staying put behind the frontlines to consolidate and shore up Russian positions – it would constitute committing aggression against Ukraine itself. Pyongyang then transitions from being a mere accomplice to a principal in Russia’s wrongdoings and an active belligerent in the war – not that Kim Jong Un bats an eye at this.
In return, South Korea’s President Yoon Suk-yeol and his administration has been feeling the pressure of responding in one way or another to the altering geopolitical, security, and legal circumstances. So far, it has limited its aid to non-lethal materiel, such as combat care medical kits and protective gear and demining hardware, and to humanitarian support for refugees and reconstruction. In 2023, Yoon mused out loud about the possibility of providing lethal weapons if Russia perpetrated “any large-scale attack on civilians, massacre, or serious violation of the laws of war.”
Russia has long since crossed this red line. In June 2024, Seoul renewed its condition for providing lethal aid to Kyiv if Moscow handed over precision-guided munitions and nuclear-related weaponry to Pyongyang.
Push came to shove, however, with North Korean boots on the war front. “I’ve had this principle of not supplying lethal weapons, but now we can more flexibly examine this option depending on North Korean soldiers’ moves,” said Yoon in late October. He also talked about adopting a “phased approach” to helping Ukraine, which could start with sending defensive weapons.
On October 30, during the press conference following a South Korea-United States security meeting in Washington D.C., South Korea’s Defense Minister Kim Yong-hyun expressed his determination to send a monitoring detachment to observe and analyze North Korea’s combat capabilities. He insisted that it was “our military’s obvious duty” and that “it would be dereliction of duty not to do so.”
Seoul already sent a delegation made up of National Intelligence Service (NIS) and defense agents to the NATO headquarters to exchange crucial intelligence – but also to potentially lay the groundwork for weapons and personnel support, given that one of them was an ammunition policy officer.
Yet, there are some legal niceties to be cleared before South Korea directly supplies weapons and dispatches uniformed personnel to Ukraine. The principal authorization rule when it comes to “exporting strategic goods” under the Foreign Trade Act and Defense Acquisition Program Act is that they be used for peaceful purposes only. This is the reason many cite in legally objecting to Yoon’s desire for weapons aid to Ukraine.
But then, “export” means “sending goods or services abroad for sale.” Hence, the presidential office once maintained that there are no statutes precluding South Korea from providing weapons aid for free.
South Korea’s Military Supplies Management Act, however, stipulates an important condition for free weapons transfers: Their absence shouldn’t adversely affect the South Korean military’s operational capability. By extension, the firearms to be shipped off most likely have been declared irrelevant and in disuse. For instance, South Korea could see off its stockpile of Hawk, Mistral, and Igla air defense missiles, since they have been all replaced by domestic models; it could also do away with old Soviet-made tanks and armored vehicles ready for decommissioning, and its abundant quantity of general purpose air-dropped bombs.
As for South Korea’s sophisticated surface-to-air missiles, other guided munitions, and shells and ammo, which Kyiv has requested of Seoul time and again, South Korea’s running low itself. In 2022, the South Korean Defense Ministry declined Ukraine’s call for military aid, citing potential limitations to its own security posture. Although South Korean bases have chronically lacked the 155mm artillery shells that have proven strategically pivotal in the current war in Ukraine, Seoul has provided some 600,000 rounds of them since late 2022 to Washington, which needed to replenish its own stockpile after helping Ukraine. Seoul may have to stop packing them off.
All the legality considered, South Korea has leeway for shipping off both defensive and offensive weapons thanks to international law that allows weapons transfers for self-defense and provided that its own defense posture remains whole. Even for sales or exports that fall under South Korea’s said authorization rule, defensive materiel such as South Korea’s cutting-edge surface-to-air missile interceptors and other air defense kits would be permissible (though not necessarily advisable) since they would be saving lives.
But the Yoon administration is mired in tougher legal debates concerning dispatching military personnel to Ukraine. The Defense Ministry wishes to send a monitoring delegation. Some or most of the personnel for the delegation would be military intelligence agents. In addition, should Yoon deliver K-weapons, it’s most likely that South Korean soldiers and technicians would have to tag along for operational training and maintenance. Service personnel would have to be armed themselves for self-defense. If security deteriorates on the field, additional deployment for their protection would be required, too.
For all this, Defense Minister Kim says it’s within his right to deploy soldiers abroad as he sees fit. As per the Defense Ministry’s Directives on Overseas Deployment of Armed Forces, he can indeed dispatch uniformed personnel on a small-scale individual basis without the National Assembly’s approval, whereas deployment of a unit is up to the legislature.
On the other hand, the Republic of Korea Constitution demands the legislature’s approval for overseas deployment of armed forces.
Granted, it’s all nebulous. The government and the opposition Democratic Party (DP) are locking horns over legal interpretations. Reading the Defense Ministry directives, it’s impossible to determine how many personnel and what scope make for an individual-basis dispatch that falls short of requiring parliamentary approval. Meanwhile, the constitution just mentions “armed forces.” It could mean any and all, regardless of the nature and size of deployment, thereby nullifying the Defense Ministry directives. After all, the constitution has a higher legal status than any other ordinary law, let alone executive directives.
The DP and one camp of jurists hold that the Yoon administration is flouting the sacred constitution that entrusted the legislature and people with calling the last shot over military affairs. The government and the other camp of legal analysts insist that the constitution implicitly limits the necessity of parliamentary approval of overseas deployment to active combat roles, just as the government stations military attachés in its embassies without consulting the legislature. For now, the DP is mulling impeaching Kim for ignoring rule of law and filing for revocation of the Defense Ministry directives at the Constitutional Court.
The finer legal points aside, the Yoon administration also has to consider broader geopolitical implications of its military aid and deployment to Ukraine. Although it’s far-fetched under international law to regard a state as a belligerent at war for simply delivering weapons aid, Russia begs to differ. In 2023, the Kremlin announced that any arms deliveries would make South Korea party to the conflict. In June 2024, Russian President Vladimir Putin said that South Korea’s supplying lethal weapons to Ukraine “would be a very big mistake.”
Some cool-headed questions await Yoon. Moscow and Seoul hadn’t really had much beef until the war and the latter’s opting for correct but unpalatable rhetoric against Putin. It’s one thing to talk the talk and dole out humanitarian aid, but quite another to field weapons and personnel while not only being perceived – however wrongly – as a participant in a conflict against two nuclear-armed states but also compromising one’s own defense capabilities in the process.
And also, is it worth the trouble to volunteer as a handyman for a war in the West that President-elect Donald Trump has said he would kibosh once in office? Is it in Seoul’s interest to run counter to the possibility of the United States changing tack under Trump 2.0?
Most importantly, South Koreans do not want Yoon to do anything with Ukraine besides the current level of humanitarian aid. A Gallup poll in October found that 8 out of 10 South Koreans frowned upon providing weapons aid to Ukraine. They will be more averse to putting boots on the ground. Yoon can’t afford to cause another uproar by going against public opinion yet again – his latest approval rating hit rock bottom at 17 percent. It’s the same figure as that of former President Park Geun-hye before she was impeached.
All things considered, Seoul’s best and safest bet would be to dangle the possibility of endowing Ukraine with some of its most effective weapons as a leverage against Russia and North Korea as a means to control and throttle the flow of North Korea’s engagement in Ukraine. Other than that really, Yoon doesn’t seem to have much to gain from grafting inter-Korean tension onto Ukrainian soil.