South Korea appointed Park Ro-byug, a veteran diplomat with expertise in European affairs, as its new ambassador to Russia.

The 58-year-old former envoy to Ukraine will replace Wi Sung-lac, who is set to retire after serving more than three years in Moscow.

Park most recently led years-long negotiations with Washington to revise their civilian atomic energy pact as the Foreign Ministry’s ambassador for nuclear energy cooperation.

The two countries clinched a deal last month to pave the way for a more stable supply of nuclear fuel, better management of used rods, research on reprocessing and future exports of reactors.

President Park Geun-hye awarded credentials to him later in the day at Cheong Wa Dae.

The ambassador will be tasked with keeping up delicate relations with Russia, which remains at loggerheads with the U.S., a top Seoul ally, over the Ukraine crisis.

Moscow has also been reaching out to Pyongyang in recent months in an apparent effort to increase its influence in inter-Korean affairs and secure investment from the South in major trilateral economic projects, such as a joint industrial district, railway, gas pipeline and power grid.

Last week, Rep. Yoon Sang-hyun of the ruling Saenuri Party briefly met with Kim Yong-nam, president of the North’s Supreme People’s Assembly, as the president’s special envoy to a ceremony in Russia marking the 70th anniversary of the defeat of Nazi Germany.

A graduate of Seoul National University, Park began his diplomatic service in 1979 and has since taken up various key positions including ambassador for energy and resources, director general for European affairs, deputy spokesperson and director for North American affairs.

He also served in Moscow in 1991 for about three years as a first secretary and acquired his doctorate in history at Russia’s Diplomatic Academy in 1993.

By Shin Hyon-hee (heeshin@heraldcorp.com)