Widening conflict North Korea's involvement in Russia's war in Ukraine is raising fears in Seoul

The video is grainy, but the message is clear. The clip, posted by NK News, purports to show North Korean soldiers in green fatigues receiving basic supplies at a training base in Russia's east, before joining Vladimir Putin's war against Ukraine.

- Justin McCurry, Luke Harding

News that Pyongyang has sent 3,000 troops to train to fight in the war has horrified Ukraine, the US, and Europe. But it has special significance in Seoul—4,500 miles from Kyiv—where North Korea is both an enemy and a next-door neighbor. What was once a European conflict is now an Asian one, too.

In return for weapons and troops, Pyongyang will secure much-needed cash and, possibly, Russian knowhow on intercontinental ballistic missiles and submarines—hardware upgrades that would dramatically intensify the threat the North already poses to its neighbors.

Events in Ukraine are being closely watched in Seoul. The soldiers are part of an eventual deployment that, according to US and Ukrainian officials, could rise to as many as 12,000. They include specially trained forces known as the "storm corps."

Yesterday, Ukraine's president, Volodymyr Zelenskyy, said North Korean troops were expected to arrive tomorrow and on Monday on the frontline in the western Kursk oblast of Russia.