North Korea says it will immediately reactivate nuclear power facilities frozen under a 1994 agreement with the United States. Pyongyang blames Washington for the move, which follows a decision to suspend fuel shipments to the energy-poor state.
Pyongyang says it will end the freeze on nuclear power facilities because it faces an acute power shortage since its fuel aid has been cut off.
North Korea's official Korean Central News Agency carried the announcement that was monitored by news organizations in South Korea.
After the United States said in October that Pyongyang admitted having an illegal nuclear weapons program, Washington and its allies halted oil shipments to North Korea.
Under a 1994 agreement, North Korea pledged to suspend its nuclear power facilities, which can produce fuel for weapons.
In return, the United States, Japan, South Korea, and the European Union sent oil to North Korea and promised to build it two nuclear reactors that can not make weapons fuel.
In its statement, North Korea accuses Washington of abandoning its obligations. The statement also says the nuclear crisis on Korean Peninsula should be resolved peacefully.
Earlier this week, Spain intercepted a ship packed with North Korean missiles bound for Yemen. Washington accuses North Korea of proliferating missile and weapons technology, but agreed to let the ship proceed to Yemen.
Japan, a key U.S. ally, says it will lodge a protest with Yemen over its purchase of Scud missiles from Pyongyang.
Government spokesman Yasuo Fukuda says such trade threatens security around the world.