Seoul: South Korean authorities announced Sunday the death of former Prime Minister Lee Hae-chan at the age of 73, while on a business trip to Vietnam.

According to Qatar News Agency, Lee, who was serving as First Vice Chairman of the Advisory Council for the Peaceful Reunification of Korea, died in a hospital in Ho Chi Minh City after suffering a heart attack, as reported by council officials.

Lee served as Prime Minister from 2004 to 2006 during the administration of former President Roh Moo-hyun. He also previously served as Minister of Education.

In October of last year, he was appointed First Vice Chairman of the Advisory Council for the Peaceful Reunification of Korea. He played a prominent role in supporting Korean unification policies aimed at strengthening political, economic, and social cooperation between North and South Korea, reducing the gap between them, and promoting peaceful dialogue and legal frameworks for a possible merger between the two countries.