Only hours before the White House announcement, US Secretary of State Mike Pompeo had seemed to lower expectations for the meeting, which Trump had earlier predicted could potentially yield an on-the-spot deal to end the Korean War.
In this photo released by the Ministry of Communications and Information of Singapore, North Korean leader Kim Jong Un, right, arrives at the Changi International Airport, Sunday, June 10, 2018, in Singapore ahead of a summit with US President Donald Trump. "We have our hostages, testing, research and all missle [sic] launches have stoped, and these pundits, who have called me wrong from the beginning, have nothing else they can say!"
Trump yesterday met Singaporean Prime Minister Lee Hsien Loong (李顯龍), was feted at lunch with an early birthday cake (his birthday is Thursday), and then went back to his hotel, the Shangri-La. "It's my honor and we will have a terrific relationship I have no doubt".
Kim replied: "Well, it was not easy to get here". As the site for their meeting, the two leaders have chosen one of Singapore's most luxurious hotels, the Capella Resort on Sentosa Island, a popular vacation spot off the southern tip of Singapore and home to Universal Studios Singapore.
Trump and Kim chatted amiably out of earshot as they walked into the building for the private meeting that preceded a full bilateral conference that included aides and advisers.
Financial markets were largely steady in Asia and did not show any noticeable reaction to the start of the summit. Trump traveled to Singapore from Canada, where he attended a meeting with other world leaders.
A USA official confirmed to CNN Trump's departure was moved up by more than 12 hours because Kim set his own departure for shortly after the summit, as first reported by Bloomberg. It came after the two leaders had spent months trading insults and threatening to wage war against each other, but this tough attitude appears to have paved the way for both sides to the negotiating table.
North Korea has previously said it was willing to discuss denuclearization, but experts have expressed concern over the varying definitions of the term held by Washington and Pyongyang.
But he added: "In the end, that doesn't matter". "We will all know soon whether or not a real deal, unlike those of the past, can happen!"
On Tuesday morning, Pompeo fed the mounting anticipation of diplomatic breakthrough, saying: "We're ready for today".
Cheering crowds greeted Kim during his stroll, and cameras from North Korea's KCNA documented his every move.
Another challenge is monitoring North Korea's nuclear scientists.
He added: "North Korea has previously confirmed to us its willingness to denuclearise and we are eager to see if those words prove honest".
Trump and his senior officials have in recent weeks been referring to Kim as "Chairman".
After the men shook hands, they repaired inside for one-on-one talks. China and South Korea would have to sign off on any legal treaty.
The young Kim is reviled as an global pariah over the 2017 murder in Malaysia of his half-brother, and the execution of hundreds of officials, including his uncle, for suspected disloyalty.
During a tweet storm that preceded the summit, Trump denounced "haters & losers" who said he should not have granted Kim - an autocrat accused of having political rivals killed the prestige of a presidential meeting without more North Korean concessions.
For North Korea, denuclearization involves the United States withdrawing troops from South Korea and pulling back the nuclear umbrella over USA allies in the region.
Kim and his government are developing missiles that can carry nuclear weapons to the U.S. and have denounced Trump as a blustery "dotard".
For Trump, achieving a momentous foreign policy success would cement his place in history.
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Trump hired him in April to replace Gary Cohn as the head of the National Economic Council, reportedly because he enjoyed Mr. Associated Press writers Zeke Miller in Singapore and Jill Colvin in Washington contributed reporting .