South Korea on Friday once again turned a cold shoulder to the North’s offer of reconciliation, demanding action to prove its resolve to break from the past pattern of overtures followed by provocations.

While welcoming Pyong­yang’s pledge to cease slander, Seoul warned the communist neighbor against “attempting to evade responsibility for its previous military provocations by suggesting leaving behind the unsavory past.”

“North Korea is insisting that its ‘crucial proposals’ don’t constitute a deceptive peace offensive,” Unification Ministry spokesman Kim Eui-do said.

“We hope it is true, but cannot help but question North Korea’s sincerity because of numerous past cases in which it staged a military provocation after a peace offensive.

“North Korea should demonstrate its sincerity through actions now, because whether or not this is a deceptive peace offensive cannot be judged through words.”

In a letter to Seoul and the country’s political parties, social groups and citizens, Pyongyang’s National Defense Commission reiterated its call on the two sides to pause slander and military exercises and work to craft measures to prevent a “nuclear holocaust.”

It also vowed to undertake further “practical behavior” to buttress its resolve for inter-Korean reconciliation, including halting “all hostile military acts on the ground, at sea and in the air.”

“We’ve already been walking down the path on our own to completely cease provocations or slander of the other side,” the letter reads.

“Our crucial proposals were neither a deceptive peace offensive, propaganda or psychological warfare targeting the same people, nor an attempt to build logic for any new provocation or correct the international community’s twisted opinion.”

Pyongyang has been stepping up its peace offensive since leader Kim Jong-un called for efforts to improve inter-Korean relations in his New Year address.

While running articles and editorials on a daily basis, the state media appears to have been trying to refrain from stringent verbal attacks, which it had frequently launched on President Park Geun-hye and other South officials.

North Korean Ambassador to the U.N. Sin Son-ho is expected to repeat the proposal at a rare news conference scheduled for early Saturday in New York. Last June, he called on Washington to accept Pyongyang’s offer of high-level dialogue to defuse tension, discuss a peace mechanism to replace the 1953 armistice and resolve the nuclear weapons issue.

But Seoul remains aloof, with Park calling for an airtight defense posture and Seoul officials bracing for a possible cross-border provocation followed by reconciliatory gestures.

The South’s hardened stance is apparently in sync with the U.S. Deputy Secretary of State William Burns’ call on the North to move toward “verifiable denuclearization” during his visit to Seoul early this week.

Kim’s first New Year’s address last year stoked optimism by stressing the need to defuse tension and halt cross-border confrontation. But hopes soon faded away as the young leader pressed ahead with an atomic test, nuclear war threats, slander and closure of a joint factory park in Gaeseong.

In 2010, Kim’s late father and longtime dictator Kim Jong-il also floated reconciliation, only to do a complete about-face months later with attacks on a South Korean corvette and a border island.

Inter-Korean relations are forecast to remain strained given upcoming Seoul-Washington military drills and Pyongyang’s unrelenting parallel pursuit of nuclear and economic development, which was again highlighted in the latest letter.

The mood has been sour particularly since the Dec. 12 execution of Jang Song-thaek, Kim’s powerful uncle who was regarded as relatively more reform-minded and closer aligned to China, which has been dissuading the Kim regime from nuclear armament. Outside the reclusive country, his sudden downfall rekindled concerns over instability within the fledgling regime.

By Shin Hyon-hee (heeshin@heraldcorp.com)