Moon's trip followed his historic summit with North Korean leader Kim Jong-un at the border village of Panmunjom on April 27. He will hold talks with US President Donald Trump on Tuesday, Yonhap news agency reported.
The two leaders have already held two telephone conversations since the inter-Korean summit, including one on Sunday.
The trip, however, also came after a series of old rhetoric from Pyongyang that accused Seoul and Washington of trying to topple its Communist regime.
North Korea abruptly suspended high-level talks with the South last week, citing an ongoing joint military exercise of the two allies. It also threatened to reconsider the Trump-Kim summit, set to be held in Singapore on June 12.
Moon and Trump will likely discuss "ways to guarantee a bright future for North Korea when it achieves complete denuclearisation", said Nam Gwan-pyo, a deputy director of the presidential National Security Office.
In the Panmunjom Declaration, the leaders of the two divided Koreas agreed to pursue complete denuclearisation of the Korean Peninsula.
In a gesture demonstrating its denuclearisation commitment, the North is moving to dismantle its only known nuclear test facility in Punggye-ri this week with dozens of journalists from South Korea, China, Russia, Britain and the US witnessing the event.
Still, its recent suspension of an inter-Korean dialogue is sending out mixed signals, also forcing many to question the sincerity of its pledge to abandon its nuclear ambitions.
During talks with Trump, Moon is expected to discuss what to expect and what not to expect from Kim based on his own encounter with the North Korean leader in April, officials from Seoul's presidential office Cheong Wa Dae said.
The officials said Moon and Trump were set to hold a one-on-one meeting where they will be accompanied by their interpreters and no one else.
"The fact that the two leaders will hold talks with no other attendants is important. It will likely be a chance for them to share their inner-most thoughts," a Cheong Wa Dae official said.
Moon will return to South Korea early Thursday.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
