Seoul slams Russian treaty with North Korea, Zelensky urges 'tangible pressure'

SEOUL, South Korea — South Korea urged Russia to stop its "illegal cooperation" with North Korea and voiced "grave concern" on Friday as Moscow moved to ratify its defence treaty with Pyongyang.

Ukrainian President Volodymyr Zelensky warned shortly after that Russia was planning to send North Korean troops into battle against his country as early as Sunday, and urged world leaders to pile "tangible pressure" on Pyongyang.

Russian lawmakers voted unanimously on Thursday to ratify a defence treaty with North Korea that provides for "mutual assistance" if either party faces aggression. It will now be sent to the upper house of parliament, the Federation Council, for approval.

According to South Korea and the United States, thousands of North Korean troops were training in Russia.

Ukraine said this week that North Korean soldiers had arrived in the "combat zone" in Russia's Kursk border region.

While stopping short of confirming boots on the ground, a North Korean official said any troop deployment to Russia would be in line with international law.

The South Korean government said it "strongly urges the immediate withdrawal of North Korean troops and the cessation of illegal cooperation".

Seoul "expresses grave concern over Russia's ratification of the Russia-North Korea treaty amidst the ongoing deployment of North Korean troops to Russia," the South Korean foreign ministry said in a statement.

Seoul said it would work with allies to "take appropriate measures" over the move, and the country -- a major arms exporter -- has suggested it could revise its longstanding policy that prevents sending weapons directly to Kyiv.

The national security advisors of the United States, South Korea and Japan on Friday discussed the North Korean troop deployment, the White House said, with the officials expressing "grave concern" at the development.

"This deployment is the latest in a series of concerning indicators of deepening military cooperation between the DPRK and Russia," US National Security Council spokesman John Kirby said, using the acronym for the official name of North Korea.

Also on Friday leaders of the Group of Seven wealthy democracies finalized details surrounding