On Monday, Russian Foreign Minister Sergey Lavrov’s asserted that a North Korean troop deployment to Ukraine could align with international law. However, experts say that statement stands in stark contrast to several foundational legal principles, particularly those outlined in the United Nations Charter and the Vienna Convention on the Law of Treaties (1969) (VCLT). The UN Charter, through Article 2(4), categorically prohibits the use of force against another state’s sovereignty unless authorized by the UN Security Council (UNSC) or justified by self-defense. As Ukraine poses no threat to North Korea, and with no UNSC authorization, any military intervention by North Korean forces would likely constitute a violation of this central tenet of international law. This principle underscores the prohibition on aggression, which serves as a bedrock for maintaining global order.

First, Article 2(4) of the UN Charter prohibits states from using force against the sovereignty and territorial integrity of another state, except in cases of self-defense or when explicitly authorized by the United Nations Security Council. Given that Ukraine has not threatened North Korea and has not consented to foreign troops on its soil, any military intervention by North Korean forces would directly infringe on Ukraine’s sovereignty. This article is considered a foundational principle of the UN Charter, intended to uphold international peace and prevent unwarranted aggression. Lavrov’s dismissal of this principle reflects a serious deviation from the legal constraints established to maintain global stability.

Additionally, Article 51 of the UN Charter limits the right of collective self-defense to situations where an armed attack has occurred against a UN member state. Since Russia’s invasion of Ukraine has been widely condemned as an act of aggression rather than legitimate self-defense, any intervention by North Korea under a collective self-defense rationale would lack legal grounding. NATO Secretary-General Jens Stoltenberg has underscored that support for Ukraine’s sovereignty aligns with NATO’s commitment to uphold international law and prevent further destabilization in Europe.

Beyond the UN Charter, the VCLT offers additional legal guardrails. Article 53 of the VCLT prohibits treaties that violate basic principles, like non-aggression, known as jus cogens norms. Any military arrangement between Russia and North Korea aiming to support actions in Ukraine would therefore be considered invalid if it goes against this fundamental norm. Moreover, Article 103 of the UN Charter specifies that UN obligations take priority over conflicting international agreements, meaning that even if Russia and North Korea sign a treaty, it cannot legally override the Charter’s principles.

Lavrov’s interpretation challenges these frameworks, risking the erosion of the rule of law by sidestepping globally accepted standards. These treaties exist to prevent conflict escalation and protect state boundaries from unauthorized interference, and ignoring these standards undermines the stability and predictability that international law strives to uphold.