"Meetings are being set up, and I want to see denuclearization of North Korea," Trump told reporters.

Asked to explain what he means by denuclearization, Trump replied: "It means they get rid of their nukes -- very simple."

"It would be very easy for me to make a simple deal and claim victory. I don't want to do that. I want them to get rid of their nukes."

While Trump has repeatedly referred to North Korea's denuclearization, Pyongyang however consistently defines the term as "denuclearization of the Korean peninsula" - code for the removal of America's military presence in the South, a condition Washington is unlikely to accept.

Amid preparations for a landmark bilateral US-North Korea summit, which could come in June, Trump had kind words for Kim, whom he once called a "madman" and "little rocket man."

"He really has been very open, I think -- very honorable," Trump told reporters from the White House Oval office, adding that the North Koreans have said they want the meeting between the two leaders "as soon as possible."

He said that "a lot of concessions have already been made" -- while stressing it was not the United States that had given ground.

"We have made no concessions," Trump said.

The talks would come after a year of heightened tensions over Pyongyang's development of nuclear weapons and an intercontinental ballistic missile that has the potential to deliver a nuclear warhead to the continental  United States.

Around the end of March or early April, CIA director Mike Pompeo traveled to North Korea and met with Kim to lay the groundwork for negotiations.

And last week, North Korea pledged to halt its nuclear and missile tests ahead of the summit.

But it has not committed to giving up its atomic weapons, which Pyongyang views as a shield against the Western overthrow of its government.

As a prelude for talks with Trump, Kim will meet with South Korean President Moon Jae-in on Friday in the border village of Panmunjom.

Trump reiterated Tuesday that he would walk away from the talks with North Korea if they are not fruitful, saying it is possible that "we're all wasting our time."

"Unlike past administrations, I will leave the table," he said. "But I think we have the chance to do something very special." (AFP)