The situation remains tense on the Korean Peninsula, where the two Koreas have been engaged in a fresh flare-up of hostilities, threatening each other with military action.
North Korea has turned down an offer by its southern neighbor to send special envoys to deescalate a situation that has arisen over anti-Pyongyang propaganda leaflets sent by defectors over the border.
The North even pledged on Wednesday to redeploy troops to the Demilitarized Zone (DMZ) that separates the two countries and to resume "all kinds of regular military exercises" there, according to the Korean Central News Agency (KCNA).
South Korea was quick to respond that the North “will pay the price" in case it takes any military action.
"Our troops express deep concern that today the General Staff of North Korea made public various kinds of military plans that are contrary to the intra-Korean agreements, the Panmunjom Declaration and the military agreement of 19 September, 2018,” a senior official from South Korea's Joint Chiefs of Staff said.
The developments came a day after Pyongyang blew up an inter-Korean liaison office building just north of its border with the South.
Outraged at Seoul over the leaflets, which are sent into the North usually by balloon over the border or in bottles by river, Pyongyang demolished the liaison office in its border town of Kaesong.
Pyongyang had earlier warned Seoul to stop the propaganda campaign and had already severed two valued hotlines with South Korean officials.
North Korea warned that the demolition would prove a first step towards "a total catastrophe" in inter-Korean relations.
It also published photos showing the liaison office before and after its demolition, alongside a series of KCNA articles and commentaries criticizing South Korea.
"The solution to the present crisis between the North and the South caused by the incompetence and irresponsibility of the South Korean authorities is impossible and it can be terminated only when proper price is paid," KCNA said.
On Monday, South Korea's President Moon Jae-in offered to send his national security adviser Chung Eui-yong and spy chief Suh Hoon to Pyongyang as special envoys for talks.
However, the North Korean leader Kim Jong-un’s sister, Kim Yo-jong, who serves as a senior official of the ruling Workers’ Party, rejected the proposal, calling it "tactless and sinister,” according to KCNA.
She further criticized Moon over his failure to implement the 2018 inter-Korean pact, saying he has "put his neck into the noose of pro-US flunkeyism."
In response, South Korea's presidential Blue House described the criticism of Moon by Kim’s sister as a “rude and senseless” act that damaged the trust built by the two Koreas’ leaders.
"We will no longer accept such unreasonable behavior," Blue House spokesman Yoon Do-han said.
North mulling resumption of border military exercises
In a separate statement on Wednesday, the North Korea’s military said it would resume military exercises in the border area.
A spokesman for the General Staff of the (North) Korean People's Army (KPA) said it would deploy regiment-level units to the Mount Kumgang tourist area and the Kaesong complex.
The North will also restart sending anti-Seoul leaflets across the border, the unnamed spokesman added.
He also said guard posts that had been withdrawn from the Demilitarized Zone under a 2018 inter-Korean agreement would be reestablished to "strengthen the guard over the front line", while artillery units, including those in naval areas, would resume "all kinds of regular military exercises."
Reacting to the announcement, ,” a senior official from the Republic of Korea's Joint Chiefs of Staff warned against the move.
“Such measures nullify all results jointly achieved for more than 20 years and efforts in the sphere of the progress of intra-Korean relations and the preservation of peace on the Korean Peninsula. If the North Korean side proceeds to real actions, it will certainly pay the corresponding price."
South Korean Defense Ministry has urged the North to abide by the 2018 agreement to cease “all hostile acts” and dismantle a number of structures along the DMZ.
South minister resigns over altercation
Separately on Wednesday, South Korea's Minister of Unification Kim Yeon-chul offered his resignation to the presidential Blue House.
Kim, who oversees engagement with North Korea, said he took "all the responsibility of worsening of inter-Korean relations,",adding that he was "sorry for not being able to fulfill many Korean people's demand and hope for peace and prosperity on Korean Peninsula."
President Moon has yet to formally accept Kim's resignation.
The two Koreas remain technically at war since the 1950-1953 Korean War ended with an armistice rather than a peace treaty.
The neighbors began fence-mending talks in January 2018.
South Korea also mediated diplomacy between the North and the United States. US President Donald Trump and Kim held three meetings but the negotiations were eventually halted owing to Trump’s refusal to relieve any of the harsh US sanctions on the North in exchange for goodwill measures by Pyongyang.
The United States has been attempting to pressure the North into giving up its nuclear weapons program.