Summit with Kim may not happen next month: Trump

WASHINGTON DC: US President Donald Trump has said there is a "very substantial chance" that his planned summit with North Korea's Kim Jong-un may not happen next month and speculated that Chinese President Xi Jinping may be behind Pyongyang's new hard line.

North Korea last week warned that it may cancel the June 12 summit in Singapore between Kim and Trump if the US insists on it giving up nuclear weapons unilaterally.

Speaking to reporters at the White House while welcoming South Korean President Moon Jae-in, Trump said that North Korea must meet conditions for the summit to go ahead though if it did not, it might happen "later".

"We're moving along. We'll see what happens," Trump said in response to a question.

"There's a very substantial chance that it won't work out. That doesn't mean that it won't work out over a period of time, but it may not work out for June 12," Trump said.

Trump said he believed Kim was "serious" about denuclearisation.

"I do think he is serious. I think he is absolutely very serious," he said, but declined to say whether he had spoken to Kim.

"They're hardworking, great people," he said of North Koreans.

"He will be extremely happy. He will be very happy" he said of Kim if the deal works out.

Earlier, Moon's national security advisor Chung Euiyong told reporters that there were 99.9 per cent chances for the summit to happen.

"We believe there is a 99.9 per cent chance the North Korea-us summit (set for June 12 in Singapore) will be held as scheduled. But we're just preparing for many different possibilities," Chung told reporters.

"We're trying to understand the situation from the North's perspective," he said when asked about changes in North Korea's rhetoric.

Trump also said that he was "little surprised" at North Korean leader Kim's "different attitude" after his second meeting with Chinese President Xi.

Xi and Kim met in the northeastern city of Dalian in an unannounced visit by the North Korean leader on May 8.

Trump said the meeting between the two leaders was not a great meeting as there has been a change in North Korea's attitude after that.

"I think that President Xi is a world class poker player. I probably maybe doing the same thing that he would do. But I will say this, there was a somewhat different attitude after that meeting, and I'm a little surprised," Trump said.

"Now maybe nothing happened, I'm not blame anybody. But I'm just saying maybe nothing happened and maybe it did. But there was a different attitude by the North Korean folks after that meeting. So I don't think it was a great meeting," Trump said.

Nobody knew about the meeting and all of a sudden it was reported that he was in China a second time, he said.

"The first time everybody knew about, the second time was like a surprise.

“And I think things changed after that meeting. So I can't say that I'm happy about it,"

Trump said in presence of South Korean President Moon.

He also asked Moon for his views on the Xi-kim meeting.

"Now President Moon may have a different opinion, I'd like to have your opinion on that. What you thought of the second meeting with President Xi, what is your feeling? You may have an opinion," Trump asked.

"I don't want to get him in trouble, he lives next to China. You know, he's not too far away," he said.

"The second meeting I think there was a little change in attitude from Kim Jong-un", he said.

"Hope that's not true, because I have a great relationship with President Xi. He's a friend of mine, he likes me, I like him. I mean that was two of the great days of my life being in China. I don't think anybody's ever been treated better in China in their history," he said.

Meanwhile, the White House said the US was preparing for the summit.

"We continue to prepare for the summit, and if they want to meet, we will certainly be ready," White House Press Secretary Sarah Sanders said.

"President Trump rightly stated that if North Korea agrees to denuclearise, that it can be a bright future for them. But we remain clear-eyed in these negotiations, but we continue to prepare, and we'll see what happens," she said.