Seoul and Washington began their latest joint military drill on Monday, laying out Operational Plan 5015 (OP 5015) for the first time, which focuses on a preemptive strike against North Korea.

Key Resolve (KR), the command post exercise (CPE) for the purpose of improving the execution of operations, will continue until March 18 while Foal Eagle (FE), a field training exercise (FTE), will be implemented by the end of April.

These joint training drills involving the two countries take place annually and are conducted in order to prepare for the potential outbreak of conflict with North Korea.

Three U.S. vessels, including