President Yoon Suk Yeol condemned North Korea's military cooperation with Russia during a summit held with Polish President Andrzej Duda in Seoul Thursday, saying North Korea's troop dispatch to Russia presents a threat that transcends borders.

Yoon said in a news conference with Duda after their bilateral talks in his office in Seoul that North Korea's troop deployment to Russia "is a clear violation of the United Nations charters and the UN Security Council resolutions." Seoul and the West suspected that North Korean soldiers would be deployed to Ukraine to fight against Ukrainian forces at the war front.

"Duda and I reached a consensus that North Korea's decision to send troops to Russia poses a security threat to the world, beyond the Korean Peninsula and Europe," Yoon said.

He also reiterated Seoul's earlier warning Tuesday that it might take phased countermeasures against the military cooperation between North Korea and Russia. An official of the presidential office said Tuesday that Seoul was even considering sending arms to Ukraine should "things go too far."

South Korea will "never tolerate" North Korea's troop deployment to the Ukraine war front line, Yoon said, adding he made it clear during the meeting that Seoul "will take phased steps in cooperation with the international community" depending on the development of the Pyongyang-Moscow military cooperation.

Yoon told Duda that South Korea would closely cooperate with Poland to increase humanitarian aid to the Ukrainian people and explore methods for peace and reconstruction in Ukraine, according to Yoon at the conference.

Also, according to Yoon's office, South Korea and Poland will hold a forum dedicated to Ukraine reconstruction cooperation between the two countries. Poland is home to the representative office of South Korea's Ukraine Reconstruction Cooperation Center.

The two leaders also discussed ways to complete a negotiation over the second batch of South Korea's K2 tank exports. South Korea in 2022 signed a $44.2 billion deal to export arms and aircraft to Poland, according to Yoon's office.

Duda is currently on a state visit to South Korea, for the first time since his predecessor.

Bronislaw Komorowski visited in October 2013, when the two countries elevated their diplomatic ties to Strategic Partnership to expand bilateral ties in the fields of defense, energy, transportation, science, technology and culture.

Yoon and Duda last met on the sidelines of the North Atlantic Treaty Organization Summit in July.