GOYANG, South Korea (AFP) — The leaders of North and South Korea agreed to pursue a permanent peace treaty and the complete denuclearisation of their divided peninsula at a historic summit Friday laden with symbolism.

The North’s leader Kim Jong Un and the South’s President Moon Jae-in embraced after signing what they called the Panmunjom Declaration, following a day that began with an emotional handshake over the Military Demarcation Line that splits their countries.

The pair issued a statement confirming their “common goal of realising, through complete denuclearisation, a nuclear-free Korean peninsula”.

They agreed they would this year seek a permanent end to the Korean War, 65 years after hostilities ended in an armistice rather than a peace treaty.

Moon would visit Pyongyang in “the fall”, the two leaders said, also pledging to hold “regular meetings and direct telephone conversations”.

But Kim did not mention denuclearisation and analysts warned that while the summit was a good first step, similar promises had been made before and much remained to be done to resolve the issue of the North’s atomic arsenal.

In coming weeks Kim is due to hold a much-anticipated meeting with US President Donald Trump — who has demanded Pyongyang give up its weapons — that will be crucial in shaping progress. Trump hailed the Korea summit as historic but warned “only time will tell”.

He implicitly claimed credit for the meeting, tweeting: “KOREAN WAR TO END! The United States, and all of its GREAT people, should be very proud of what is now taking place in Korea!”

The Panmunjom Declaration capped an extraordinary day unthinkable only months ago, as the nuclear-armed North carried out a series of missile launches and its sixth atomic blast, earning itself new sets of UN Security Council sanctions.

Kim and Trump had traded personal insults and threats of war, sending tensions soaring before Moon seized on the Winter Olympics to try to broker dialogue, beginning a dizzying whirl of diplomacy that led to Friday’s meeting in the Demilitarised Zone.

Kim said he was “filled with emotion” after stepping over the concrete blocks that mark the border, making him the first Northern leader to set foot in the South since the Korean War ceasefire in 1953.

At his impromptu invitation, the two men briefly crossed hand-in-hand into the North before beginning the summit, only the third of its kind.

The truce village of Panmunjom was the “symbol of heart-wrenching division”, Kim said afterwards, but if it became “a symbol of peace, the North and South that have one blood, one language, one history and one culture, will return to becoming one”.

He pledged the two Koreas would ensure they did not “repeat the unfortunate history in which past inter-Korea agreements… fizzled out after beginning”.

In the declaration, the two sides said they would seek meetings this year with the US and possibly China — both of them parties to the 1953 ceasefire — “with a view to declaring an end to the war, turning the armistice into a peace treaty, and establishing a permanent and solid peace regime”.

But agreeing a treaty to formally close the conflict will be complicated — both Seoul and Pyongyang claim sovereignty over the whole of the Korean peninsula.

The two previous Korean summits in 2000 and 2007, both of them in Pyongyang, also ended with displays of affection and similar pledges, but the agreements ultimately came to naught.

Moon welcomed the North’s announcement of a moratorium on nuclear testing and long-range missile launches as “very significant”, calling it “an important step towards complete denuclearisation of the Korean peninsula.”

But how much progress was made on the nuclear issue remained unclear.

Pyongyang has always insisted it needs nuclear weapons to defend itself against a US invasion, and its past references to denuclearisation of the “Korean peninsula” have been code for the removal of US troops from the South and the end of its nuclear umbrella over its security ally — prospects unthinkable in Washington.

The North is demanding still unspecified security guarantees to discuss its arsenal, while Washington is pressing it to give up its weapons in a complete, verifiable and irreversible way. Affirming a commitment to “denuclearisation of the Korean Peninsula”was “not new”, said MIT political science professor Vipin Narang, “historic summit notwithstanding”.

But he added: “Reaffirming it is better than not reaffirming it.”

Paul Haenle of the Carnegie-Tsinghua Center in Beijing said it was “really just the first step in broader diplomatic efforts”.

“Similar to a game of chess, this move opens up a series of possible developments but in many ways, the hard work really begins now.”

Before signing the declaration, Moon and Kim held a symbolic tree planting ceremony near the demarcation line.

The soil came from Mount Paektu, on the North’s border with China, and Mount Halla, on the South’s southern island of Jeju.

It was a far cry from the last time the South Korean leader was on duty for a tree-related event in the DMZ, in 1976, when he had a supporting role in a monumental US and South Korean show of force after Northern soldiers killed two US officers trying to prune a poplar.

After the planting, Kim and Moon spoke alone for more than half an hour in an open-air tete-a-tete, the younger North Korean leader nodding and listening attentively to the former special forces soldier — who has long advocated dialogue.