The appeal comes a week after Pyongyang announced a "new strategic weapon." President Moon Jae-in said security on the Korean Peninsula depends on resolving international tensions, and urged Kim Jong Un to visit Seoul.
President Moon Jae-in has said South Korea must strengthen its relationship with Pyongyang, and has called for fresh talks with North Korean leader Kim Jong Un.
In an annual New Year's speech in Seoul on Tuesday, Moon also pledged further efforts to facilitate US-North Korean dialogue.
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The South Korean president said he regretted the past year's stall in negotiations with the North, and said he was prepared to meet Kim repeatedly if needed, despite Pyongyang's abandonment of its nuclear and missile test moratoriums.
The relationship between the two countries has waned in recent years due to international sanctions that restrict most business with North Korea, leading Pyongyang to ignore Seoul's recent proposals for cooperation.
"I hope South and North Korea can make efforts together so that the conditions for Chairman Kim Jong Un's reciprocal visit can be arranged at an early date," Moon said. "I suggest South and North Korea put our heads together."
'Nothing to talk' about
Since the collapse of Kim's summit with US President Donald Trump in Vietnam last February, the North has repeatedly lashed out at the South, saying it has "nothing to talk" about with Seoul.
"In a time of deadlock in US-North Korea talks — and where we are even concerned about a step backward in inter-Korean relations — we are in desperate need of practical ways to improve inter-Korean cooperation," Moon said.
The South Korean leader said the two countries could achieve progress through strengthened cooperation, suggesting that a joint 2032 Olympics bid by the North and the South could prove to be a unifying event, as would finishing the inter-Korean railroad.
Moon also proposed that Pyongyang and Seoul consider a unified team at the Tokyo Summer Olympics in July, which would see athletes from both sides march together at the opening ceremony. Athletes from the two Koreas took part together at the opening and closing ceremonies of the Pyeongchang Winter Olympics in South Korea in 2018.
Moon urges US-N. Korea diplomacy
Washington has refused to ease sanctions until North Korea agrees to take more concrete actions to dismantle its nuclear weapons and ballistic missile programs.
On January 1, Kim announced that Pyongyang will no longer abide by its earlier nuclear promises and would continue to develop such weapons unless the US changed its policy toward North Korea. Kim declared that "the world will witness a new strategic weapon" in the near future, but he also indicated there was still an opportunity for negotiations with Washington.
"The momentum for US-North Korea talks must continue," Moon said. "Provocations and threats are not helpful for anyone."
The last visit between Moon and Kim took place in Pyongyang in September 2018.
"I'm willing to meet repeatedly and talk ceaselessly" with the North, Moon said Tuesday.
mvb/cmk (AFP, Reuters)