South Korea has vowed to take action in response to growing military cooperation between Russia and North Korea, despite Pyongyang’s denial of reports that it has sent troops to support Russia’s war in Ukraine. Officials in Seoul have described the alliance between the two countries as a global threat and committed to working with international allies to counter the partnership, which could include providing arms to Ukraine.

On Monday, South Korea summoned the Russian ambassador after accusing North Korea of sending 1,500 soldiers to fight alongside Russian forces in Ukraine. Although North Korea dismissed the claims as “groundless rumours”, Seoul rejected this denial, promising to implement phased countermeasures. The National Security Council warned that North Korean involvement in Russia’s “illegal war of aggression” poses a significant security threat not only to South Korea but to the international community as a whole.

While South Korea has so far provided non-lethal aid to Ukraine, including demining equipment, officials indicated they may consider supplying weapons for defensive purposes as part of their response. If the situation escalates further, the possibility of offensive weapons is also on the table. North Korea has continued to deny the accusations from both South Korea and the United States, with a representative at the UN dismissing them as attempts to damage the image of North Korea and undermine its relations with Russia.