The spokesman said the North will "intensify unspecified military countermeasures" unless the U.S. stops conducting military drills on the peninsula and pulls out all the military assets needed to threaten the North with a nuclear attack.
The renewed vitriol, which included the threat for unspecified retaliatory action, followed a Monday protest by about 250 people in downtown Seoul, where effigies of Kim Il Sung and his late son and successor, Kim Jong Il, were burned. Such protests are fairly common in South Korea, and though Monday's was held on the holiday that North Korea calls "The Day of the Sun," some analysts suggested North Korea was using it as a pretext to reject calls for a dialogue with the South, at least for the time being.
North Korea often denounces protests like the one held Monday, but rarely in the name of the Supreme Command, which is headed by Kim Il Sung's grandson and North Korea's overall leader, Kim Jong Un.
The North's statement said it would refuse any offers of talks with the South until it apologized for the "monstrous criminal act."
"If the puppet authorities truly want dialogue and negotiations, they should apologize for all anti-DPRK hostile acts, big and small, and show the compatriots their will to stop all these acts in practice," the statement said. North Korea's official name is the Democratic People's Republic of Korea, or DPRK.
This year's festivities were mostly low key, with Pyongyang residents gathering in performance halls and plazas and taking advantage of subsidized treats, like shaved ice and peanuts. Last year's anniversary — the centennial of Kim Il Sung's birth — was marked with days of immense festivities and a massive military parade.