North Korea is preparing for a massive firepower demonstration by mobilizing multiple rocket launchers for regime founder Kim Il-sung's birthday on Tuesday and the North Korean Army's anniversary on April 25.

The exercise is to replace the usual interminable parade.

"There are no signs of the North preparing for a parade at Mirim Airport or Sunan International Airport in Pyongyang," a government source here said. "So it's unlikely that there'll be a massive parade either on Kim Il-sung's birthday or on army founding day."