North Korea on Wednesday repeated its denunciation of an ongoing South Korean-US military exercise, calling it a rehearsal for "a preemptive nuclear attack" on the communist country.
Tens of thousands of US and South Korean troops Monday began an 11-day drill known as Ulchi Freedom Guardian.
"Lurking behind them is a dangerous scheme for aggression to mount a preemptive nuclear attack on the DPRK (North Korea) and to conquer it anytime when an opportunity presents itself under the pretext of coping with an event of contingency in the Korean Peninsula," a foreign ministry spokesman said.
The spokesman noted that the exercise was staged after Washington promised to offer "extended deterrence" to protect South Korea.
"The US is so foolish as to try to stifle the ideology and system of the DPRK by force of arms," the North's spokesman said on official media.
The developments prove that North Korea's decision to bolster its self-defensive deterrent, a reference to its nuclear programme, was the right option, he said.
"The DPRK will closely follow every movement of the US and the South Korean authorities and adopt a tough measure against any provocation", he added.