President Donald Trump said that he wants to see North Korea eventually give up its nuclear weapons programme, but adds he is not in any rush because US relations with Pyongyang are good going into next week's summit.
I have no pressing time schedule," President Trump said.
He said his second meeting with North Korea's leader Kim Jong Un on February 27-28 in Hanoi, Vietnam, would be "very exciting", but did not disclose details of what he hoped would be achieved.
He said he discussed the upcoming summit during a phone call earlier in the day with South Korea President Moon Jae-in and will speak on Wednesday with Japan's Prime Minister Shinzo Abe.
"I look forward to being with Chairman Kim and I think a lot of things will come out of it," President Trump said.
"We had a tremendous first summit - it was really breaking the ice, but a lot of things came from that, including good relationships."
President Trump noted that North Korea has not tested any rockets or missiles or nuclear weapons in months and said as long as testing has ceased, he is in no rush.
"I think I would like to see ultimately denuclearisation of North Korea. I think we will see that ultimately," President Trump said. "I have no pressing time schedule."
He said some people, including members of the media, want to see speedy progress on denuclearisation.
"I really believe that North Korea can be a tremendous economic power when this is solved," he said, referring to Mr Kim's pledge of denuclearisation.
"Their location between Russia, China and South Korea is unbelievable. I think that North Korea and Chairman Kim have some very positive things in mind. And we'll soon find out.
"As long as there's no testing, I'm in no rush. If there's testing, that's another deal."