South Korea's presidential office has expressed hope that the upcoming United States-North Korea summit will be a success as the two leaders are very committed to a positive outcome.

A senior presidential official said on Sunday that Seoul is calmly watching the situation, saying that the meeting between U.S. President Donald Trump and North Korean leader Kim Jong-un is a critical summit that could end confrontation and a war that has been going on for seven decades.

The official said that the two leaders are arriving in Singapore on Sunday probably because they want to thoroughly prepare for their meeting.

The official also dismissed the possibility of President Moon Jae-in joining Trump and Kim later for a trilateral summit in Singapore.