Nuclear deal may take more than one meeting with North Korea's Kim Jong Un: Donald Trump

US President Donald Trump said on Thursday it may take more than one meeting with North Korean leader Kim Jong Un to seal a denuclearization deal and that he would like Pyongyang to dismantle its nuclear weapons program as quickly as possible under any agreement.

Trump, in a brief interview with Reuters aboard Air Force One as he flew to Texas for Republican fund raising events, said he was still hoping for a summit with Kim on June 12 in Singapore.

The president emphasized that it may take more than one meeting to reach an agreement.

"I'd like to see it done in one meeting. But oftentimes that's not the way deals work," Trump said.

"There's a very good chance that it won't be done in one meeting or two meetings or three meetings. But it'll get done at some point. It may get done really nicely and really intelligently, or it may not get done intelligently. It may have to be the hard way," he said.

The president said he believed Kim wanted a deal.

"But I think it'll get done in a very smart, organized fashion and I think that Kim Jong Un wants to see it also. And I'm going to be very happy when the day arrives when we can take sanctions off, and have a very good relationship with the entire Korean Peninsula," Trump said.

US-ally South Korea and North Korea have technically been at war for decades, even though the Korean War's military combat ended in 1953, because a peace agreement was never signed.

The president said he will most likely be visited by North Korean envoy Kim Yong Chol on Friday at the White House after the official's meetings with US Secretary of State Mike Pompeo in New York.

The North Korean official is carrying a letter to Trump from Kim Jong Un. "I look forward to seeing the letter and I look forward to June 12 where hopefully we can make progress," Trump said.

Disputes between Washington and Pyongyang led Trump to announce last Thursday he was canceling the meeting with Kim, only to say the following day that it could still go ahead. The days since have seen a flurry of diplomatic efforts to get the summit back on track.

In a letter to Kim last Thursday cancelling the summit, Trump accused North Korea of "open hostility," but urged Kim to "call me or write" if he had a change of heart.

In his interview with Reuters, the U.S. president said a nuclear deal with North Korea would have to cover its missile program. "It means missiles," Trump said.

He said he wanted to see denuclearization occur at a rapid pace.

"I'd like to see a total denuclearization in as quick a period of time as is practicable," he said. "You're talking about machinery, you're talking about things that can't necessarily happen immediately but they can happen in as rapid a fashion as they can happen. That's what I want to happen."

North Korea has made advances in missile technology in recent years but Trump has sworn not to allow it to develop nuclear missiles that could hit the United States.