President Yoon Suk Yeol has ordered his aides to make thorough efforts to maintain an optimal national security posture, assessing the current security situation surrounding the Korean Peninsula to be grave.

Senior Presidential Secretary for Public Relations Lee Do-woon said on Monday that Yoon issued the order during a meeting with presidential aides.

He explained the president's order is in regards to maintenance of a firm readiness posture against military and economic security impacts from North Korea and Russia's recent signing of a comprehensive strategic partnership treaty as well as the crisis in the Middle East.

Earlier on Monday, top nuclear envoys from South Korea, the U.S. and Japan condemned "in the strongest possible terms" deepening Pyongyang-Moscow military cooperation.

They said the advancement of the partnership, as highlighted by the treaty, should be of grave concern in maintaining peace and stability on the Korean Peninsula and upholding the global nonproliferation regime.