Sept. 21 (UPI) -- South Korean President Yoon Suk Yeol warned during an address to the United Nations General Assembly that Seoul and its allies will not "stand idly by" if Russia gives North Korea technical assistance with its nuclear and missile programs.
Yoon made the remark during his keynote address at the U.N. General Assembly in New York on Wednesday evening, shortly after a six-day visit by North Korean leader Kim Jong Un to Russia that prompted widespread speculation over a potential weapons deal.
Last week, the White House expressed concern over a "budding arms deal" between Pyongyang and Moscow, citing intelligence that Kim was planning to supply Russia with artillery for its war against Ukraine.
Kim, meanwhile, is reportedly seeking advanced technology for the North's weapons programs, including its efforts to launch a military spy satellite into orbit.
Yoon on Wednesday called the North's nuclear and missile programs a "direct and existential threat" to South Korea and a "serious challenge" to peace around the world.
"If the DPRK acquires the information and technology necessary to enhance its WMD capabilities in exchange for supporting Russia with conventional weapons, such a deal between Russia and the DPRK will be a direct provocation," Yoon said, referring to North Korea by its official acronym.
"The Republic of Korea, together with its allies and partners, will not stand idly by," he said.
In a follow-up move, South Korea on Thursday slapped unilateral sanctions on 10 individuals and two entities involved in the North's illegal weapons trade with other countries, including Russia.
Included on the blacklist were North Korean Defense Minister Kang Sun Nam and former top general Pak Su Il, according to Seoul's foreign ministry.
Kang was part of the delegation that traveled with Kim to Russia last week, where the North Korean leader held a summit with President Vladimir Putin and visited several military sites to view advanced fighter jets, bombers and missiles.
Kim met with Defense Minister Sergei Shoigu in Vladivostok and discussed "strengthening the strategic and tactical coordination, cooperation and mutual exchange between the armed forces of the two countries," according to North Korean state media.
The Kremlin has denied that any deals for military or technical cooperation were struck during the visit.
Yoon also echoed concerns about Russia raised by Ukrainian President Volodymyr Zelensky, who said Wednesday that Moscow has abused its permanent seat on the U.N. Security Council and called for the removal of its veto power.
"It is paradoxical that a permanent member of the U.N. Security Council ... would wage war by invading another sovereign nation and receive arms and ammunition from a regime that blatantly violates Security Council resolutions," Yoon said.
"In such a situation, the call to reform the U.N. Security Council would receive a broad support," he added.
The Russian Embassy in Seoul expressed "deep regret" over Yoon's remarks on Thursday and accused him of joining the "propaganda campaign initiated by Washington ... aimed at discrediting Russian-North Korean cooperation."
In a post on its Facebook page, the embassy urged South Korea to "base their actions on a sober and objective assessment of the current situation, as well as the negative consequences of Seoul's continued pursuit of the anti-Russian line."