South Korea on Monday "strongly warned" against North Korea's plan to launch a satellite in the coming weeks, vowing to make Pyongyang pay "due prices" if it goes ahead with the launch.

"We strongly warn against North Korea's announcement of provocative actions that threaten regional peace and urge them to immediately withdraw their illegal launch plan," Lim Soo-suk, spokesperson of Seoul's foreign ministry, said in a statement.

Lim warned the North will be made to pay "due prices" and suffer "pain" if the launch goes ahead.

Japanese media reported that the North notified Tokyo it will launch a satellite-carrying space rocket between May 31 and June 11. The launch is banned under UN Security Council resolutions, because it uses ballistic missile technology.

South Korea held an emergency meeting of the National Security Council earlier.

Last week, Pyongyang announced the completion of preparations to mount its first military spy satellite on a rocket, raising speculation that the North may launch it as early as June. (Yonhap)