South Korean President Yoon Suk-yeol said he would discuss with NATO leaders the distinct threat North Korea poses to Europe by deepening military ties with Russia, warning that Moscow must choose between the two Koreas where its true interests lie.

It "depends entirely" on where Russia wants to take future ties with South Korea, Yoon said, adding that Seoul would make a decision on weapons support for Ukraine based on how a new military pact between Moscow and Pyongyang plays out.

"Military cooperation between Russia and North Korea poses a distinct threat and grave challenge to the peace and security on the Korean Peninsula and in Europe," Yoon said.