North Korea condemns the joint military exercise that South Korea, Japan, and the USA completed on Saturday.
Pyongyang calls the military exercise a "Asian version of NATO" and warns of "catastrophic consequences".
The condemnation comes on Sunday, a day after the allies completed the three-day exercise, called "Freedom's Fence".
The leaders of the USA, South Korea, and Japan agreed at a trilateral summit last year to conduct annual military exercises together, as a sign of the countries' unity in the face of North Korea's nuclear threat and China's increasing regional influence.
Seoul rejected Pyongyang's accusations.
"It is absurd that North Korea, the primary source of tensions on the Korean Peninsula, criticizes the exercise by categorizing it as an 'Asian NATO'", said South Korea's Defense Department in a statement.