The defense chiefs of South Korea and the US agreed Friday to continue close cooperation for a nuclear-free peninsula in the face of North Korea's recent peace gesture.

In phone talks with Secretary of Defense Jim Mattis, South Korea's Defense Minister Song Young-moo emphasized his government's firm stance on resolving the North Korean nuclear issue through a "phased, comprehensive" approach in tandem with sanctions and dialogue, according to his ministry.

A strong alliance with Washington is the basis of the policy, Song added.

The minister assured Mattis that the South will continue close coordination with the US on the North, as the two Koreas plan to hold high-level talks next week on Pyongyang's participation in the PyeongChang Winter Olympics.

He expressed hope that military tensions will be eased in Korea through the successful hosting in February of the Winter Games and inter-Korean dialogue, which would contribute not only to the denuclearization of the peninsula but also peace and stability in Northeast Asia.

The Pentagon chief reaffirmed Washington's "ironclad" security commitment to South Korea, including its powerful "extended deterrence."

He agreed that the North Korean nuclear issue should be resolved peacefully and stressed the importance of the international community maintaining sanctions and pressure on Pyongyang for sincere denuclearization talks.

Their phone conversation came a day after President Moon Jae-in and his American counterpart Donald Trump agreed to adjust the schedule for the Key Resolve and Foal Eagle defense drills to avoid the overlap with the Winter Olympics. (Yonhap)