The White House said in a statement on Saturday after Trump's meeting with Chinese President Xi Jinping that they and Kim will strive "to see a nuclear free Korean Peninsula".
The last defection involving North Koreans occurred in May when two civilians aboard a small boat defected to the South across the Yellow Sea.
Donald Trump has said he is likely to meet Kim Jong-un in January or February and that three sites for their second meeting are under consideration. The South Koreans have expressed hope the visit - which would be a first for a North Korean leader - could happen by the end of this year.
A South Korean train, carrying 28 government officials and railway experts, passes through the demilitarized zone (DMZ) in Paju, Gyeonggi, on Friday.
North Korean and South Korean soldiers are pictured during an operation to reconnect a road across the Military Demarcation Line inside the Demilitarised Zone (DMZ) separating the two Koreas (Novemeber 22, 2018).
Videos show people taking cover as Alaska quake struck
Officials have now cancelled a tsunami warning for southern Alaska that was issued following the 7.0-magnitude natural disaster . Kilgore said only 15 or 16 quakes of magnitude 6 or greater have been recorded during the past century in the same region.
More than 30,000 North Koreans have fled to the South since the 1950-53 war on the peninsula ended in an armistice instead of a peace treaty. It will travel to Wonsan and other areas on the east coast for a joint survey of 745 miles of North Korea's railway system and facilities, the ministry said. A freight train that ran from Dorasan Station in the South to Panmun Station in the North was stopped on November 28, 2008, after inter-Korean relations became strained.
It comes as the North and South Korea have pushed to implement a wide-ranging military agreement reached in September to reduce tensions across their border.
Last weekend, South Korea announced that the United Nations Security Council sanctions committee on North Korea had granted an exemption allowing for the joint survey to take place.
They agreed on the need for "maintaining vigorous enforcement of existing sanctions to ensure the DPRK understands that denuclearisation is the only path", Sanders said, using the North's official name, the Democratic People's Republic of Korea. "The two leaders agreed Chairman Kim Jong Un's visit to Seoul would provide additional momentum to their joint efforts to establish peace on the Korean Peninsula", Moon's chief press secretary Yoon Young-chan said.
The prospect of Kim's visit to Seoul had been in doubt amid the stalled denuclearization talks between Pyongyang and Washington, with the two sides in a deadlock over who should make the first move since Kim and Trump held their first summit in June.