Trump heads for DMZ after inviting Kim to 'Say hello'

US President Donald Trump heads for the Demilitarised Zone dividing the two Koreas on Sunday and a possible impromptu summit with North Korean leader Kim Jong Un, in what would be a remarkable diplomatic spectacle.

Trump did not mention Kim when he took to Twitter early Sunday to say that his schedule for the day would include a speech to US troops and a "long planned" visit to the DMZ.

Their first meeting in Singapore last year took place in a blaze of publicity -- the first-ever encounter between a leader of the nuclear-armed North and a sitting US president, whose forces and their allies fought each other to a stalemate in the 1950-53 Korean War.

That summit produced a vaguely-worded pledge about denuclearisation, but a second meeting in Hanoi in February intended to put flesh on those bones broke up without agreement.

Contact between the two sides has since been minimal -- with Pyongyang issuing frequent criticisms of the US position -- but the two leaders have exchanged a series of letters and Trump turned to Twitter on Saturday to invite Kim to a third diplomatic date.

"If Chairman Kim of North Korea sees this, I would meet him at the Border/DMZ just to shake his hand and say Hello(?)!," Trump tweeted from Osaka in Japan, where he was attending a G20 summit before flying to Seoul.

He later said he would have "no problem" stepping into the North with Kim -- in what would be a dramatic re-enactment of the extraordinary scene last year when the young leader invited South Korean President Moon Jae-in to walk over the Military Demarcation Line that forms the border between the Koreas.

"Sure I would, I would. I'd feel very comfortable doing that. I'd have no problem," Trump told reporters.

It was not clear whether Kim would attend the rendezvous.

In an unusually fast and public response, within hours of Trump's tweet the North's official KCNA news agency quoted Vice Foreign Minister Choe Son Hui as saying the offer was "a very interesting suggestion" but that no official request had been received.

Cheong Seong-chang, a senior researcher at the Sejong Institute in Seoul, said the KCNA comments indicated Kim had "practically accepted" Trump's invitation.

"If he (Kim) isn't interested he would not release such a statement to begin with."
Later Saturday, when he was asked about the meeting at a dinner with Moon in Seoul, he said: "We're gonna see. They're working things out right now."
"If Trump and Kim meet & can announce some kind of interim agreement, that's great. If they meet and don't, that's ok too. If in the end they don't meet, it's good that Trump offered to."