The brief declaration also commits Washington to unspecified "security guarantees" to North Korea and pledges the establishment of "a lasting and robust peace regime on the Korean Peninsula."
US Secretary of State Mike Pompeo and North Korean officials are set to hold follow-up negotiations "at the earliest possible date," according to the declaration.
Read more: What's in the document that Kim and Trump signed?
Few detailsSpeaking to reporters at the signing ceremony, Trump said he expected denuclearization to start "very, very quickly." Sitting next to the president, Kim said both leaders "decided to leave the past behind" and that "the world will see a major change."
Read more: Donald Trump-Kim Jong Un Singapore summit — As it happened
But the declaration contained few details about how North Korea would denuclearize, how the US would verify that effort, what type of security guarantees the US had committed to or whether a "peace regime" would include a treaty to formally end the 1950-53 Korean War. It also made no reference to crippling US economic sanctions against Pyongyang that Washington passed in response to the North's nuclear and ballistic missile tests.
'They will be doing things'Speaking at a follow-up press conference, Trump said US and international officials would verify the North's denuclearization, but that negotiators did not have enough time to put in more details in the joint declaration.
Verification has been a sticking point in previous talks between the US and North Korea. Negotiations broke down in 2009 after Pyongyang and the US disagreed about how to verify a 2005 North Korean pledge to give up its nuclear program.
Trump also said sanctions would remain in effect until the US could be "sure the nukes are no longer a factor" and that the US would suspend its joint military exercises with South Korea while negotiations continue.
Asked about whether he had broached the North's poor human rights record, Trump said he had discussed the topic "relatively briefly" with the North Korean side. "They will be doing things," he added.
'Prelude to peace'The joint declaration between Trump and Kim capped off a historic summit between two leaders who only months ago had threatened to go to war and exchanged a series of public insults.
Trump and Kim struck a cordial and optimistic tone from the beginning, with both men opening proceedings by shaking hands on a red carpet in front of a wall of American and North Korean flags. Trump promised reporters "a great discussion," while Kim said the summit was "a good prelude to peace."
At the end of the summit, Trump said he had developed a "very special bond" with Kim and invited the North Korean leader to the White House. "I learned he's a very talented man," Trump said, adding, "we are going to take care of a very dangerous problem for the world."
amp, law/rc (Reuters, dpa, AFP, AP)
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