Chief Cabinet Secretary Yasuo Fukuda called for calm Tuesday following North Korea's threat to abandon the Korean War armistice if the United States imposes sanctions on it.

"It is in line with (Pyongyang's) way of thinking, that views sanctions as an act of war," the government spokesman told a news conference. "We must take it calmly."

Earlier Tuesday, North Korea said it has "no option but to take a decisive step to abandon its commitment" to the 1953 Korean War armistice if the U.S. imposes sanctions in retaliation for its development of nuclear weapons.