People watch a TV at Seoul Railway Station, Jan. 20, showing a file image of a North Korean missile launch broadcast during a news program. AP-Yonhap

The government emphasized Thursday that dialogue and diplomacy are the only key to building peace on the Korean Peninsula in response to North Korea's thinly veiled threat to scrap a self-imposed moratorium on nuclear weapons and long-range missile tests.

The North held a high-profile politburo meeting of the ruling Workers' Party the previous day and decided to consider restarting "all temporally-suspended" activities to brace for a "long-term confrontation" with the United States, according to Pyongyang's state media.

"The government is closely monitoring the North's latest moves with a sense of tension," the Ministry of Unification that handles inter-Korean affairs said in a statement. "We will thoroughly prepare for possible deterioration of the situation while closely coordinating with other countries to keep the situation on the Korean Peninsula under stable control," it added.