The warning is the latest threat against Washington and Seoul over joint US-South Korean military drills now underway that the North sees as a dress rehearsal for invasion.
The ultimatum, issued by a unit of the Korean People's Army and carried by the North's state media Saturday, also demanded that Park publicly execute officials responsible for what it says are plans to attack its leadership.
Separately today, a North Korean propaganda outlet posted a video depicting a nuclear attack on Washington, DC.