Allies South Korea, Japan, and the United States have denounced plans by North Korea to launch a long-range rocket.
The North said the launch would be a test of satellite technology.
North Korea is preparing to mark the centenary of founder Kim Il Sung's birth next month.
In a statement, South Korea's Foreign Ministry said such a launch would be a violation of a UN Security Council resolution that bans the North from conducting launches using ballistic-missile technology.
The statement said such a launch by North Korea would be a "grave provocation threatening the peace and security of the Korean Peninsula."
In Japan, chief cabinet secretary Osamu Fujimura said Tokyo will urge North Korea not to carry out the launch.
And the U.S. State Department called North Korea's plan "highly provocative," saying it would run counter to the North's recent pledge to refrain from long-range missile launches.
North Korea's announcement came after Pyongyang agreed last month to suspend uranium enrichment, halt nuclear and long-range missile tests, and permit a return of United Nations weapons inspectors in exchange for much-needed food aid.
With AFP and Reuters reports