'Blood alliance' How Ukraine war is stoking tensions

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

- Justin McCurry and 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 - 7,300km from Kyiv - where North Korea is a both an enemy and a nextdoor neighbour. 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 intensify the threat the North already poses to its neighbours.

Events in Ukraine are being closely watched in Seoul. "North Korea's troop deployment signalled that the war in Ukraine is no longer a conflict that has little to do with South Korea," the Korea Times said in an editorial.

The soldiers are part of an eventual deployment that, according to US and Ukrainian officials, could rise to as many as 12,000.

"The massive troop dispatch indicates that Russia-North Korea ties are moving beyond the provision of rifles, shells and short-range missiles to the level of a blood alliance," the Korea Herald said.

Last Friday, Ukraine's president, Volodymyr Zelenskyy, said North Korean troops were expected imminently on the frontline in Russia's western Kursk oblast. He described the arrival of North Korea's military as an "obvious escalatory move" and called on world leaders to put "tangible pressure" on Moscow and Pyongyang.

Ukraine has occupied a small salient inside Russia for two and a half months. North Korean troops are expected to bolster Russia's ongoing attempts to kick out Ukrainian forces.