This is about as close to an ultimatum to Russia that you will see from the Yoon administration:

National security adviser Chang Ho-jin said Sunday that South Korea will not be bound by anything with regard to its assistance to Ukraine if Russia provides North Korea with precision weapons.
Director of National Security Chang made the remark during a TV appearance, underscoring the point that Seoul’s decision on whether to provide weapons to Ukraine depends on how Russia’s military cooperation with North Korea goes.
“I would like to emphasize that it all depends on what Russia will do,” Chang said on KBS TV. “Will there be any line remaining for us if Russia gives precision weapons to North Korea?”
Chang’s remark means South Korea could provide lethal weapons to Ukraine if Russia crosses the line.
Yonhap
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