Anti-war activists hold cards after a press conference to demand the peace on the Korean peninsula on the eve of the 70th anniversary of the outbreak of the Korean War in Seoul, South Korea, Wednesday, June 24, 2020. North Korean leader Kim Jong Un suspended his military's plans to take unspecified retaliatory action against South Korea, state media said Wednesday, possibly slowing a pressure campaign against its rival amid stalled nuclear negotiations with the Trump administration. The sign reads "Let us end the war." (AP Photo/Ahn Young-joon)

SEOUL, Korea, Republic Of - On both sides of the world's most heavily armed border Thursday, solemn ceremonies will mark the 70th anniversary of the outbreak of a war that killed and injured millions, left large parts of the Korean Peninsula in rubble and technically still continues.

This anniversary may be especially bitter for South Korean President Moon Jae-in, who'd hoped that an unprecedented swirl of engagement and diplomacy between the rivals over the last two years could fundamentally change their relationship. Amid renewed threats of violence from Pyongyang, Moon's ambitious engagement plans are fading fast.

North Korea has shown mixed signals in recent days. In a fit of symbolic rage, it blew up an empty liaison office with the South last week. But this week it appeared to shift speed by suspending purported plans to take unspecified retaliatory action against South Korea.

Whatever the North's intentions, the promising flurry of diplomacy that saw North Korean leader Kim Jong Un meet multiple times with U.S., Chinese and South Korean leaders in a high-stakes play to settle a disarmament-for-aid deal has been replaced by a revival of ideological warfare.

Seoul is now desperate to prevent relations from spiraling into crisis but also seems short on ideas on how to do so.

North Korea over the past week has threatened to abandon a military agreement aimed at reducing tensions, and censured the South over lack of progress in bilateral co-operation and for failing to stop activists from floating anti-Pyongyang leaflets across the border.

The North’s recent steps follow months of frustration over Seoul’s unwillingness to defy U.S.-led sanctions over its nuclear weapons program and resume inter-Korean economic projects.

Moon has proposed joint anti-virus efforts against COVID-19 and offered to send humanitarian aid, but that's unlikely to satisfy Kim as he struggles to keep afloat an economy crippled by sanctions and a pandemic that has hampered exchanges with China, the North’s main ally and economic lifeline.

The North may want a South Korean commitment to resume operations at a shuttered jointly-run factory park in the North Korean border city of Kaesong, which was where the liaison office was located, or to restart South Korean tours to the North’s Diamond Mountain resort. But Seoul can't take such steps without rattling the international sanctions regime against the North and hurting the South Korean alliance with Washington, which has stuck to a hard line.

“South Korea doesn’t have many options,” said Nam Sung-wook, a professor at the South’s Korea University who formerly headed a think-tank affiliated with Seoul’s main spy agency.

“We are the same Korean people but also (war) enemies. Achieving reconciliation and co-operation between the Koreas is not as easy as you might think.”

Moon, the son of North Korean war refugees who preaches that the South should lead international efforts to deal with the North, had been credited with co-ordinating a diplomatic push to settle the nuclear standoff. His envoys shuttled between Pyongyang and Washington to help set up the first meeting between Kim and President Donald Trump in Singapore in June 2018.

But he has faced criticism of over-optimistically misreading Pyongyang's signals. Seoul ran into credibility problems once it became clear, during negotiations, that Kim had no intention of easily dealing away the nukes he likely sees as his strongest guarantee of survival.

While Moon insisted that progress in inter-Korean relations could help create nuclear breakthroughs between Pyongyang and Washington, the North doesn’t seem to see much value in Seoul if the South fails to squeeze concessions from Washington on Pyongyang's behalf.

It remains to be seen whether Kim’s decision this week to reverse his purported decision on an unspecified military action affects the North’s plan to resume propaganda warfare.

If Kim does opt for military action, it may be a resumption of military exercises or an order to have vessels deliberately cross the disputed western maritime border between the Koreas, which has seen bloody skirmishes in the past. However, any action is likely to be measured in a way to avoid a full-scale retaliation by the U.S. and South Korean militaries.

Condemning Seoul over North Korean refugees in the South floating anti-Pyongyang leaflets across the border, the North said Monday it printed 12 million of its own propaganda leaflets to be dropped over the South in what would be its largest ever anti-Seoul leafleting campaign.

The North has a history of escalating provocations before pulling away from the brink and offering diplomacy aimed at extracting concessions from the South.

A provocative run of nuclear and missile tests in 2017 saw Kim and Trump exchange crude insults and threats of nuclear annihilation.

Tensions eased after Kim used the 2018 Winter Olympics in South Korea to initiate diplomacy with Moon and Trump.

The Korean leaders met three times that year and issued vague pledges for a nuclear-free Korean Peninsula without describing when and how it would occur. They also vowed to restart South Korean tours to Diamond Mountain and operations at the Kaesong factory park when possible, expressing hope that sanctions would end.

Those projects remain shelved amid stalled negotiations between Washington and Pyongyang, which began to implode after the second Kim-Trump meeting last year in Vietnam, where the Americans rejected North Korea’s demands for major sanctions relief in exchange for a partial surrender of its nuclear capabilities.

It would require major concessions for Moon’s government to save its diplomacy with the North, said Hong Min, an analyst at Seoul’s Korea Institute for National Unification. Suspending South Korea’s summertime military exercises with the United States and legally punishing anti-Pyongyang activists for leafleting, which will trigger freedom of speech debates in the South, would barely get the North interested.

Others question whether the recent diplomacy is worth saving amid fading denuclearization prospects.

“South Korea needs to quickly shift its focus from developing inter-Korean relations to managing inter-Korean hostilities,” said Cheong Seong-Chang, an analyst at South Korea’s Sejong Institute. “If North Korea takes a hard swing (at the South), we should also sternly respond to make them realize they suffer too when inter-Korean relations turn hostile.”

News from © The Associated Press, 2020