The office of South Korean President Moon Jae-in confirmed on Monday that President Donald Trump had called Moon from Singapore for a final chat before his scheduled meeting with North Korean dictator Kim Jong-un on Tuesday morning.

A spokesman for the Blue House, South Korea’s presidential palace, confirmed the two world leaders spoke on Monday regarding Trump’s meeting with Kim Jong-un, scheduled to begin at 9 a.m. local Singapore time on Tuesday.

The spokesman reportedly described the call as unexpected and relayed that Moon told Trump he hopes he and Kim will be able to give the world the “gift” of peace through extensive conversations, hopefully leading up to the official end of the Korean War.

While there have been no active hostilities in the Korean War since an armistice signed in 1953, neither side ever signed a peace treaty, meaning the United States remains technically at war with North Korea.

“President Moon and President Trump agreed Trump and Kim will be able to make a great achievement if the two leaders come together to find a common denominator through frank discussions,” spokesman Kim Eui-kyeom told reporters, according to South Korea’s Yonhap News Agency. Yonhap notes that Secretary of State Mike Pompeo’s first stop out of Singapore will be Seoul, where he is expected to brief Moon and senior officials on what transpired between Kim and Trump.

Moon himself remarked on the summit on Monday, reportedly referring to the meeting as “the encounter of the century.”

“I hope the summit will produce agreements related to the denuclearization of the Korean Peninsula and put an end to confrontational relations [between Washington and Pyongyang],” South Korean newspaper Joongang Ilbo quoted Moon as telling reporters. “President Trump put into action his strong resolve to set in place a peace plan on the Korean Peninsula and solve the North Korean nuclear problem.”

“I look forward to audacious decisions by the two leaders as they accept each other’s demands [at the summit meeting], so that the hopes held by people around the world for a peaceful era on the Korean Peninsula can be realized,” Moon reportedly concluded.

JoongAng also provided more details about the direct talks between Trump and Moon, reporting that they spoke for about 40 minutes, starting at 4:30 p.m. local Singapore time Monday.

Moon Jae-in has met personally with Kim Jong-un twice in the past year, once in March for the first such meeting between leaders of North and South Korea and once two months later in a surprise encounter. Moon reportedly did not discuss with Kim human rights or the suffering of North Korean prison camp victims, instead opting for a discussion about a potential end to the Korean war and reestablishing some form of diplomatic relation between the two sides.

Following his two meetings with Kim, it appeared Moon was attempting to get himself invited to the June 12 summit between Kim and Trump.

“The discussions are just getting started, so we are still waiting to see how they come out, but depending on their outcome, the president could join President Trump and Chairman Kim in Singapore,” an unnamed South Korean government official said in late May, adding that Moon was the one who proposed a “three-way summit” with the leaders. As the United States and China are signatories to the armistice that ended hostilities in the Korean War, North and South Korea cannot end the Korean War without both countries being present and signing onto any peace treaty.

JoongAng Ilbo reported this weekend that it was “unlikely” Moon would appear at the Singapore summit.

Trump and Kim are expected to use the meeting Tuesday to get a feel for what the other one wishes to see emerge from any bilateral relationship. According to North Korea’s state media outlet, the Korean Central News Agency (KCNA), the two will discuss a “permanent and durable peace-keeping mechanism” on the Korean peninsula as well as “denuclearization,” which KCNA did not specifically define.

The United States is seeking a complete, irreversible end to the illegal North Korean nuclear program, which for decades, the Kim regime insisted was necessary for its survival. Under Kim Jong-un, North Korea spent much of 2017 threatening to use nuclear weapons to destroy the American mainland, threats the Trump regime would like to eliminate forever.

Trump has made clear he does not expect a clean solution to decades of conflict to arise from one meeting, however, and has floated the possibility of several meetings with Kim. JoongAng reported on Monday that “a source in Singapore familiar with the process” believes Kim has already invited Trump to Pyongyang for another meeting in July.

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