Russia’s Deputy Foreign Minister Andrei Rudenko visited South Korea to discuss the Ukrainian war and bilateral ties, Seoul’s foreign ministry said Sunday, as the two countries trade increasingly heated rhetoric over the nuclear-armed North. Rudenko, Russia’s deputy foreign minister handling Asia-Pacific affairs, met his South Korean counterpart Chung Byung-won on Friday, Seoul’s foreign ministry said in a statement. Chung expressed Seoul’s “grave position” on Moscow’s growing military cooperation with Pyongyang and urged Russia to take “responsible actions,” the statement said. His visit came …