Kim Jong Un on Friday will become the first North Korean leader to cross the military demarcation line dividing the two Koreas since the end of the Korean War in 1953, Seoul says. Kim will set off on foot at 9:30 am (0030 GMT) to meet South Korean President Moon Jae In, presidential chief of staff Im Jong Seok said Thursday at a briefing on the following day’s schedule. The North Korean delegation, which includes Kim’s sister Kim Yo Jong, who in February attended the Pyeongchang Olympics opening ceremony, will attend an official welcoming ceremony at 9:40 am. The first talks at the historic inter-Korean summit, which will be held at the Peace House, just south of the border at the joint village of Panmunjom, will begin at 10:30 am after Kim signs a guestbook and poses for commemorative photos, Im said. Later in the day, the two leaders will plant a pine tree dating from 1953 when the Korean War armistice was signed, before an agreement is signed and announced, he added. At 6:30 pm Kim and Moon will attend a welcoming banquet, to be followed by a farewell ceremony during which video showing images of the Korean Peninsula will be projected onto the Peace House. The talks – the third inter-Korean summit after meetings in 2000 and 2007 – will set the tone for a meeting between Kim and US President Donald Trump, expected to take place late May or early June. Regional tensions were ratcheted up last year after North Korea launched a series of ballistic missile tests and a nuclear test, while Kim and Trump traded a series of threats and bizarre insults. But at the beginning of this year Kim launched an unexpected programme of diplomatic outreach, which included the North’s attendance of the Winter Olympics in South Korea. South Korea said Friday’s summit would deal with “the denuclearization of the Korean Peninsula, the establishment of permanent peace on the Korean Peninsula, and the advancement of inter-Korean relations.” But the issue of denuclearization will be tricky. “When it comes to denuclearization, it is very difficult which level can be agreed upon,” Im admitted at Thursday’s briefing. Kim last week announced that he would halt nuclear and missile tests effective immediately and shut down a nuclear test site. But he said nothing about getting rid of his existing nuclear arsenal, which he described as a “powerful treasured sword.” The lifting of international sanctions is dependent on him giving up his nuclear weapons. NATO Secretary General Jens Stoltenberg said in Brussels on Thursday that the summit was “a first important step towards a negotiated peaceful solution to the crisis on the Korean peninsula.” He cautioned however that “until we see concrete changes in North Korea’s actions, we must continue to put pressure on North Korea and … continue with the sanctions.” Regarding a possible US-North Korea meeting, Trump said on Thursday that: “It could be that I walk out quickly – with respect.” “It could be that, maybe, the meeting doesn’t even take place. Who knows? But I can tell you right now, they want to meet,” he told broadcaster Fox.