The U.S. and South Korea have agreed to explore ways “to enhance regional security cooperation,” the U.S. defense secretary said Thursday, as Washington signals its interest in expanding the scope of alliance concerns beyond the Korean Peninsula to contain China.

U.S. Secretary of Defense Lloyd Austin made the remarks following a meeting with his South Korean counterpart Suh Wook in Seoul, at which the two sides also approved guidelines on updating their wartime operation plans.

“We discussed a wide range of topics, including our unity in the face of the threat from North Korea and our progress in our bilateral