Trump says sanctions on North Korea to stay in place

US President Donald Trump and South Korea's Moon Jae-in agreed on Thursday on the importance of nuclear talks with North Korea, but the two leaders aren't completely aligned on whether sanctions would pressure Kim Jong Un to give up his nuclear weapons or drive him away from the negotiating table.

Trump, in his first meeting with Moon since the unsuccessful US summit with Kim in Hanoi, said the United States wanted to keep economic sanctions in place to pressure Kim to denuclearise. But Trump said he retained good relations with Kim and didn't rule out a third summit or taking steps to ease food or other shortages in the repressive nation.

North Korea, which has suspended nuclear tests and missile launches, has been pressing for sanctions relief but has not taken meaningful steps towards dismantling its nuclear weapons programme.

Trump and Kim have met twice, in Hanoi in February and Singapore last June, building goodwill but failing to agree on a deal to lift sanctions in exchange for North Korea abandoning its nuclear and missile programs.

“It could happen. A third summit could happen. And it’s step by step. It’s not a fast process. I’ve never said it would be. It’s step by step,” Trump said.

"We want sanctions to remain in place," Trump said at the White House. "I think that sanctions right now are at a level that's a fair level."

Moon, for his part, has called for an easing of sanctions, including those holding back joint economic projects between North and South Korea. But he didn't speak about the sanctions issue as he and Trump spoke with reporters at the start of their talks.

Trump said he would favor easing those sanctions at the right time but added, "This isn't the right time." He said he was open to discussing smaller steps, such as helping to ease North Korea's humanitarian problems, but that, in general, the US wanted sanctions to remain.

"There are various smaller deals that maybe could happen," Trump said.

"You could work out step-by-step pieces, but at this moment, we're talking about the big deal. The big deal is we have to get rid of the nuclear weapons."

Trump and Moon discussed the possibility of the South Korean leader having an inter-Korean summit with Kim soon as a way to boost dialogue between the US and North Korea on denuclearisation.

Kim and Moon met three times last year and Kim promised to visit South Korea in return for the South Korean leader's visit to Pyongyang in September.