The foreign ministry announced Yun's appointment Monday, highlighting the time he served as deputy minister for economic affairs from 2017 to 2020, TBS news reported.
He also led negotiations with Tehran over Iranian funds frozen in South Korean banks due to US sanctions.
"We expect that Yun will play a key role in stably managing and enhancing bilateral relations with Iran at a time when the South Korea-Iran relationship has become more important than ever," a ministry official said.
Yun entered the foreign service in 1987 and has worked at missions to the United Nations, the Organization for Economic Cooperation and Development, Laos, Myanmar, and Uzbekistan.
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