After some fiery North Korean rhetoric, Mr Trump announced the summit would not be held.
"Very good news to receive the warm and productive statement from North Korea". One sign, written in English, read "withdraw USA troops".
China, Pyongyang's sole major ally, urged the two foes to "show goodwill", while UN Secretary-General Antonio Guterres called on the parties to keep talking, as did host Singapore, and Russia's President Vladimir Putin held out hope the talks would eventually take place. Kim said the cancellation of the talks shows "how grave the status of historically deep-rooted hostile North Korea-US relations is and how urgently a summit should be realized to improve ties".
USA defense and intelligence officials have repeatedly assessed the North to be on the threshold of having the capability to strike anywhere in the continental US with a nuclear-tipped missile - a capacity that Trump and other US officials have said they would not tolerate.
Ruling party lawmaker Choo Mi-ae said she remains hopeful.
The comments reflected a broadly shared perception inside the White House and State Department that the two leaders still want to get together and there will be a meeting eventually.
Joe Hagin, the deputy chief of staff for operations at the White House, was scheduled to travel to Singapore this weekend to make preparations. "We'd like to do it", he said. "We didn't want to go to a meeting just for the sake of going to a meeting".
Klingner also said he thinks the summit can move forward after Friday's more gracious statements, but likely not on June 12 as planned.
Kick-starting talks, however, will face a number of obstacles, including a possible credibility gap created by the dramatic about-face.
Less than a year after the two leaders traded threats of nuclear war, the back-and-forth over whether the summit will even happen reflects both Trump's lead-from-the-gut style of decision-making and North Korea's long-standing penchant for unpredictable behavior.
Dozens of worldwide journalists left North Korea on Saturday after observing the demolition of the underground tunnels in Punggye-ri, where all of the North's six nuclear tests were conducted including its latest and largest in September.
It was unclear if Pompeo, who has traveled twice to Pyongyang for meetings with Kim, would continue to play a role in the negotiations.More news: Woman poops on floor, throws her dung at restaurant employee
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First Vice-Foreign Minister Kim Kye Gwan called the decision "unexpected" and "regrettable".
While the White House has clearly stated that North Korea must take significant steps toward complete denuclearization in a limited time frame before any sanctions can be relaxed or significant rewards given, Pyongyang has called for a "synchronous" process of disarmament in which gradual steps towards denuclearization are met with concurrent USA economic and security concessions.
On Thursday, he blamed the North's "open hostility" for the cancellation of his talks with Kim Jong-un. "We are watching developments carefully", Presidential Blue House spokesman Kim Eui-gyeom said.
Kyodo News reported senior North Korean officials were also seen en route to Singapore.
Analysts say Kim's diplomatic outreach in recent months after a flurry of nuclear and missile tests in 2017 indicates he is eager for sanctions relief to build his economy and the worldwide legitimacy the summit with Trump would provide.
"If there is a summit ..." "And that could mean they start launching missiles all over again".
"Everyone has to lower their expectations for a summit".
For weeks now - ever since TV pictures of a charming-looking Kim Jong-un captivated South Koreans - people have flocked to observation posts like the one at Odusan to peer, curiously, into North Korea.
Trump welcomed the statement on Twitter early Friday.