The United States and South Korea signed a new joint operation plan last year specifically designed to counter North Korea’s rapidly advancing nuclear weapons capabilities and changing security dynamics in the region, the commander of the U.S. Forces Korea (USFK) disclosed Wednesday.

“Last year, we took a significant step forward in our combat readiness when the new combined Operations Plan (OPLAN) was signed,” Gen. Xavier Brunson, commander of the USFK and the combined U.S.-South Korea forces, said in a statement submitted to the House Armed Services Committee hearing.

Brunson was joinedby Adm. Samuel Paparo, commander of U.S. Indo-Pacific Command