North Korea has threatened to launch a “sacred war” if South Korea and the United States go ahead with planned annual military exercises.

The North's National Defense Commission called the maneuvers “an outright challenge to the peace and security of the Korean peninsula and an explicit act of destruction.”

The statement also hinted at possible nuclear retaliation, saying nuclear weapons are not the monopoly of the U.S. and that Pyongyang has “war means more powerful than the U.S. nukes.”

The two allies plan to jointly hold military drills called “Key Resolve” from February 27 to March 9, and “Foal Eagle” from March 1 to April 30. Each exercise will mobilize thousands of U.S. and South Korean troops to practice tactics that would be used to protect the South from invasion.

South Korea and the U.S. regularly hold military exercises to bolster their readiness against a possible North Korean invasion. Still, the North routinely denounces military drills in the South as rehearsals for invasion.

U.S. Forces Korea issued a press release this week saying that the exercises “are carried out in the spirit of the October 1, 1953, ROK-U.S. Mutual Defense Treaty and in accordance with the Armistice” that ended the Korean Conflict.