North Korea threatened Monday it would reconsider an earlier agreement with South Korea to hold the high-level talks planned for later this month, according to the Unification Ministry.
Pyongyang alleged the Seoul government has failed to prevent a group of right-wing activists from flying anti-North Korea propaganda leaflets across the border.
North Korea delivered the message in a fax through the military hotline to the presidential office of Cheong Wa Dae.
The message sent in the name of the North's powerful National Defense Commission said the two Korea's should "think about whether the high-level dialogue could be held under such a mood."
The National Security Council (NSC), the southern counterpart of the commission, renewed its stance that the Seoul government cannot stop such civilian activities without appropriate legal grounds.
The ministry said North Korea claimed in the message that the government did nothing to prevent the activists from launching the leaflet balloons.
"This shows the South is overlooking the North's request to keep the dialogue mood afloat," the ministry cited the North as saying.
Ministry spokesman Lim Byeong-cheol said in a briefing that it is not fair for North Korea to raise the issue of the leaflet campaign. "Freedom of expression is the core value guaranteed in our constitution. So the North should not attempt to use the matter as a precondition for the already agreed inter-Korean talks," he said.
Regarding the government's response to the leaflet campaign, he said the government has been doing what it should to guarantee the safety of the people in the event of possible conflicts between local residents and the civilian activists."
North Korea has been showing an extremely sensitive response to the leaflets as they contain pictures and statements severely criticizing the reclusive regime and its leader Kim Jong-un. Many of them contain explicit and seemingly provocative accusations about Kim's wife Ri Sol-ju, with focus on her alleged relations with other men before getting married to Kim.
The North has also been desperate to protect its leader amid a growing move in the United Nations to bring him to the international court in connection with his alleged violations of human rights.
Touching upon the envisioned high-level talks, Lim said, "The government's stance has not changed at all ― the inter-Korean dialogue should proceed as planned."