The nation’s top nuclear envoy, Wi Sung-lak, says South Korea and Japan will seek action against North Korea through the U.N. Security Council if the North goes ahead with a planned rocket launch.

Wi on Monday met with Japan’s Foreign Minister Hirofumi Nakasone in Tokyo to discuss the issue.

After the meeting, Wi said that Nakasone and he agreed that a missile launch by North Korea would violate a U.N. Security Council resolution and that the issue would be discussed by the Security Council if the North proceeds with the launch.

Wi added that the two sides also agreed on the need to swiftly resume the six-party nuclear talks.