Seoul and Washington on Friday revealed their decision to deploy the Terminal High Altitude Area Defense (THAAD) system in the South following recent North Korean missile and nuclear tests.
The two allies have not yet revealed exactly when and where the system, which fires projectiles to smash into enemy missiles, would be deployed but said they were in the final stage of selecting a potential venue.
"The DPRK will take a physical counter-action to thoroughly control THAAD... From the moment its location and place have been confirmed in South Korea," the artillery bureau of the North's military said in a statement, according to the official Korean Central News Agency (KCNA).
It also warned the South of "miserable self-destruction" as a consequence of deployment of the THAAD system.
More From This Section
"We once again warn the enemies that it is the steadfast will of the KPA to make merciless retaliatory strikes to reduce south Korea to a sea in flames, debris once an order is issued," the statement said.
Seoul denounced the "ridiculous threats" by the North, which had staged serious provocations including a nuclear test in January and a long-range rocket launch in February.
Pyongyang also test-fired what appeared to be a submarine-launched ballistic missile a day after the announcement by Seoul and Washington, sparking swift international condemnation.
Saturday's launch followed Pyongyang's back-to-back tests of a powerful new medium-range Musudan missiles on June 22 -- theoretically capable of reaching US bases as far away as Guam.
Tensions are high high since Pyongyang carried out its fourth nuclear test in January, followed by a series of missile launches that analysts said showed the North was making progress toward being able to strike the US mainland.