South Korean President Moon Jae In is set to unveil a "New Southern Policy" aimed at boosting ties and economic cooperation with Asean countries, as he embarks on his first South-east Asian tour tomorrow.

He will outline his vision in two major speeches in Indonesia and the Philippines, confirming talk that he wants to upgrade South Korea's ties with Asean to the same level as its relations with four powers - the United States, China, Japan and Russia.

While South Korea is a dialogue partner with Asean, the latter was not a priority. South Korea's pivot to South-east Asia is part of its moves to diversify its trade links after an economic fallout from a year-long diplomatic row with China.

"(Mr) Moon has stressed the importance of bolstering ties with Asean nations throughout his presidential campaign (earlier this year)," said his economic adviser Kim Hyun Chul, noting that Asean is South Korea's second-largest trade partner after China.

Official figures show that bilateral trade hit a record high of US$71.8 billion (S$98 billion) in the first half of this year and is set to exceed last year's US$118.8 billion, as more South Korean firms, such as retailers Lotte and E-mart, move investments out of China to Vietnam and Indonesia.

Mr Moon will fly tomorrow to Jakarta, where he will meet Indonesian President Joko Widodo and then speak about his Asean policy at a business forum on Thursday. On Friday, Mr Moon will leave for Vietnam's Danang to attend the Asia-Pacific Economic Cooperation summit and meet Chinese President Xi Jinping on the sidelines.

His final stop is the Philippines, where he will attend Asean meetings and have talks with Chinese Premier Li Keqiang. There, Mr Moon will speak at a business forum next Monday about his vision to establish a Korean-Asean community in the future.

Dr June Park from the Seoul National University Asia Centre said it would be key for South Korea and Asean countries to identify "optimal areas for cooperation" and leverage each other's comparative advantages.