Korea Investment Corporation’s president and chief executive Choi Chong-suk has resigned for personal reasons, and chief investment officer Lee Dong-ik has assumed his duties on an interim basis.

The sovereign wealth fund has already started a search for Choi’s full-time replacement and expects to have one in place by the end of the year.

KIC, which had $61.6 billion in AUM as of March 31 by AsianInvestor figures, did not respond to requests seeking comment by press time.

Lee was nominated to a three-year-term as CIO in April 2012, succeeding Scott Kalb. Lee was the first Korean national to serve the sovereign wealth fund as CIO, after Kalb, an American, and Guan Ong, a Malaysian who now runs Blue Rice Investment Management. Lee initially joined KIC as head of its private-market group in 2008.

Early in his career, he served as a market analyst at the International Finance Corporation, the private-sector arm of the World Bank. Between 1997 and 2001, Lee worked at Samsung Life, heading the insurer's overseas investment division. And from 2001 to 2006, he oversaw investments at STIC Investments, a local private equity fund. He has also worked as a financial adviser to Korean firm Key Partners.

Choi was nominated CEO of KIC in July 2011 after what was a long-publicised search for a successor for Chin Young-wook, who retired after completing a three-year long term.

Choi, who previously worked in the private sector, was at the time a surprise choice for the CEO post, given the shortlist included senior government officials from the Ministry of Finance and Strategy, one of KIC’s two shareholders, alongside the central bank.

He has also worked at Korea Exchange Bank and Hana Bank Group and its affiliates. His other roles include co-chairman of now-defunct joint-venture Hana Allianz Asset Management and chairman of Allianz Global Investors’ Korea business.

Choi’s father is Choi Kya-ha, former president of the Republic of Korea in the late 1970s.