Russian President Vladimir Putin, second from left, and North Korea's leader Kim Jong-un examine a launch pad during their meeting at the Vostochny cosmodrome outside the city of Tsiolkovsky, about 200 kilometers from the city of Blagoveshchensk in the far eastern Amur region, Russia, on Wednesday, Sept. 13. AP-Yonhap

South Korea's foreign ministry on Friday called on Russia to "transparently explain" its recent dealings with North Korea amid growing speculation of an arms supply deal at last week's bilateral summit.

"If it (Moscow) will not engage in such worrisome military cooperation with North Korea, Russia should transparently explain (its dealings with North Korea) so that the international community could find it acceptable," a ministry official said.

The comments were made in response to a statement made by the Russian Embassy in Seoul on the previous day upon President Yoon Suk Yeol's speech condemning military cooperation between Pyongyang and Moscow at the United Nations General Assembly this week.

In a Facebook message in English, the embassy expressed "deep regret" that Yoon "joined the propaganda campaign initiated by Washington and picked up by the American and South Korean media aimed at discrediting Russian-North Korean cooperation."

North Korean leader Kim Jong-un and Russian President Vladimir Putin held a summit at the Vostochny space center in Russia's Far East last Wednesday, raising concerns the North may have reached a deal to supply ammunition for Russia's war in Ukraine in exchange for food aid and the transfer of weapons technology. (Yonhap)