Further details of what would be the first meeting between a serving USA president and a North Korean leader would be released shortly, he added. It is this historical background that makes Trump's seemingly spontaneous decision on March 8 to meet Kim so astonishing - it reverses decades of American policy.
The Saturday change saw North Korea set its clocks 30 minutes ahead, doing away with "Pyongyang Time", which was created in 2015.
According to reports, Trump, while leaving White House for Texas on Friday said to the reporters, "We now have a date and we have a location". But momentum for diplomacy has built this year as the rival Koreas have patched up ties. The meeting would be an extraordinary development after more than a year of insults and escalating tension between the United States and nuclear-armed North Korea.
Clocks show time in Seoul, left, and Pyongyang at the Peace House in the demilitarised zone in the border village of Panmunjom between North and South Korea on April 25.
"I feel sad to see that there are two clocks hung on the wall in the Peace House, one for Seoul time and the other for Pyongyang time", Kim reportedly said at the talks, speaking of a "painful wrench". And a lot of things have happened, with respect to the hostages.
90 per cent of the planet is breathing in polluted air
But other pollution sources, including construction dust and the burning of crop stubble in the winter, continue unchecked. Of the 20 most polluted cities, 14 are in India , while two cities - Peshawar and Rawalpindi - are in Pakistan.
Earlier in the day, Bolton rebuked a New York Times article which reported that Trump was looking for options to scale back the number of USA troops in South Korea, calling it "utter nonsense". Kim then invited Moon to cross briefly north with him before they returned to the southern side. Moon also said that Kim does not view the removal of US troops from South Korea as a precondition of him removing nuclear weapons from the peninsula.
But a U.S. National Security Council official told a visiting South Korean official in Washington via telephone the report was false, the South Korean presidential office said in a statement.
"The president has not asked the Pentagon to provide options for reducing American forces stationed in South Korea", Bolton said. That session was considered among the last steps before Trump could schedule a face-to-face meeting with Kim.
Trump hinted that the release of Kim Dong Chul, Kim Hak Song and Tony Kim was in the offing, but again was sparing on the details. "As I said yesterday, stayed tuned".