Donald Trump gave a press conference to media gathered in Singapore following his meeting with Kim Jong-un.
The pair signed a document that included pledges for North Korea to ‘work towards complete denuclearisation of the Korean Peninsula’ and establish a peace process.
He also assured reporters that human rights issues had been discussed "at pretty good length", but didn't give more details.
"We’ll be doing something on it. It’s rough. Ultimately we’ll agree to something but it was discussed at length outside of the nuclear situation," he said.
In the press briefing, Trump thanked Mr Kim, who he referred to as Chairman Kim, as well as Moon Jae-in, president of South Korea, and President Shinzo Abe of Japan.
He added he’d be speaking to President Moon “after I’ve finished”.
“My meeting what honest, direct, and productive. We got to know each other well,” he said.
North Korea should 'engage with the world'
“We’re ready to start a new history and a new chapter between our nations. ”
He also spoke of his hopes that Mr Kim would destroy all North Korea’s nuclear capabilities and “engage with the rest of the world”.
“Adversaries can become friends,” said Trump.
“There is no limit to what North Korea can achieve when it gives up its nuclear weapons and engages with the rest of the world, that really wants to engage.
“Chairman Kim will be remembered as the chairman who ushered in a new era of prosperity for his people.”
'All Koreans living in harmony'
He assured the assembled press that Mr Kim was on his way back to North Korea and would start implementing the new terms as soon as possible.
“I know for a fact that when he gets back he’ll start a process that will make a lot of people very happy,” he said.
He also managed a sly dig at his White House predecessors, saying: “We also agreed to vigorous negotiations to implement the agreement as soon as possible.
“This isn’t the past, this isn’t another administration that never got is started and never got it done.”
He spoke of his hopes for “a future where all Koreans can live together in harmony”.
“Anyone can make war, but only the truly courageous can make peace.
“To realise their amazing destiny, to reunite their national family [of North and South Korea], the menace of nuclear weapons must be removed.
“In the meantime, the sanctions will remain in place.”
Listen to Professor Scott Lucas discuss with Julia Hartley-Brewer above
Otto Warmbier 'did not die in vain'
A journalist then asked him why he was comfortable referring to Mr Kim as “talented” despite Trump previously accusing the North Korean regime of torturing Otto Warmbier.
Warmbier was a US high school student who visited North Korea on a guided tour in 2016 and was imprisoned for allegedly attempting to steal a propaganda poster.
While incarcerated, he fell into a coma, the cause of which was never officially determined although his parents said he was brutally tortured, and took legal action against North Korea earlier this year.
Warmbier died after being repatriated to the US last year.
“He is talented to take on a situation at that age, 26,” Trump responded.
“Otto Warmbier, he’s a very special person, his parents are good friends in my life.
“I think without Otto, this would not have happened. After Otto, a lot of people began to focus on what was going on, including North Korea. Otto did not die in vain.”
Professor Scott Lucas, international politics expert from the University of Birmingham, told Julia Hartley-Brewer that caution should be exercised over the pledges.
"North Korea has not had to give up anything tangible," he said, pointing out that they'd already committed to 'working towards' denuclearisation in a meeting with South Korea.
"While Kim as in the room, Trump couldn't say anything about human rights. After he left, he answered the question."