South Korean President Lee Jae Myung pledged to "respect" North Korea's political system and said Seoul would not seek unilateral reunification in a speech to mark Liberation Day.

South Korea will end some military activities along its border with North Korea, President Lee Jae Myung said on Friday, in his government's latest effort to improve ties between the neighbouring countries still technically at war.

South Korean President Lee Jae Myung vowed Friday to "respect" North Korea's political system and build "military trust", a day after Pyongyang said it had no interest in improving relations with Seoul.