SEOUL, SOUTH KOREA – APRIL 27: South Korean president, Moon Jae-in (R) and North Korean leader Kim Jong-un (2nd R) take a walk after planting a commemorative tree in the Peace House building at the southern side of the truce village of Panmunjom, South Korea on April 27, 2018. Kim Jong-un is the first North Korean leader to enter South Korea since the end of the Korean War in 1953.