This photo, taken on Nov. 12, shows Foreign Minister Cho Tae-yul speaking during a press briefing at the government complex in Seoul. (Yonhap)

Any attempt to end North Korea's military support for Russia's war in Ukraine needs to proceed in parallel with a push to denuclearize the North, Seoul's chief diplomat said Monday, stressing Pyongyang's backing for Moscow is reshaping security dynamics in the Indo-Pacific and Europe.

In a message to an annual forum, Cho voiced optimism that the South Korea-US alliance will continue to "thrive" under the incoming Trump administration, despite concerns that President-elect Donald Trump's America First credo could weaken partnerships with allies and partners.

"Its troops and weapons deployed to Russia are directly threatening Europe and reshaping security dynamics in the Indo-Pacific and Europe," Cho said in the video message for the South Korea-US Strategic Forum co-hosted by the Center for Strategic and International Studies and the Korea Foundation.

"Thus, any attempt to end the war in Ukraine would be inadequate without addressing North Korea's illicit assistance to Russia's war efforts. And any attempt to stop North Korea's military support for Russia's aggression would be incomplete without a parallel push to denuclearize North Korea," he added.

A deepening military alignment between Moscow and Pyongyang has been a source of growing concern for both Seoul and Washington as the North's material and personnel support to Russia could expand the war in Ukraine and the two countries' cooperation could have security implications on the Korean Peninsula.

On the future of the alliance between Seoul and Washington, Cho expressed his confidence, offering a set of reasons, including the fact that American support for the alliance "cuts across party lines."

"The importance of the Nuclear Consultative Group and of strengthening extended deterrence is widely understood," he said. "Support runs deep for further expanding the alliance's horizon to cyberspace and outer space and for broadening our trade and investment partnership to include shipbuilding and servicing, semiconductors, batteries, AI and nuclear domains, among others."

NCG is a key nuclear deterrence body between Seoul and Washington, while extended deterrence refers to Washington's commitment to using the full range of its military capabilities, including nuclear weapons, to defend its Asian ally.

The foreign minister also reiterated the Yoon Suk Yeol administration's determination to assume responsibilities commensurate with Korea's strength, saying that it "comports very well with the expectation that allies must pull their weight."

"Seoul, too, is committed to maintaining peace through strength and making sure that its defense spending is robust. Only three US allies and partners -- Israel, Greece, Poland -- spend more on defense as a percentage of GDP than Korea," he said.

In addition, Cho underscored the importance of cooperation with Japan and other partners to confront global challenges.

"Deepening ROK-US-Japan trilateral cooperation and advancing collaboration with like-minded nations across the Indo-Pacific and in Europe, whether through NATO or the G7, will remain as critical as ever in addressing this and other complex challenges facing our world," he said.

ROK stands for South Korea's official name, the Republic of Korea. (Yonhap)