North Korean leader Kim Jong-un, center, visits a training base of the North Korean military's special operations forces, Oct. 2, in this photo carried by the North's official Korean Central News Agency, Oct. 4. Yonhap

The likelihood of North Korea deploying a large number of combat forces to support Russia in its war against Ukraine remains low amid mounting speculation that North Korean troops are involved in the conflict, experts said Thursday.

Instead, observers suggested that Pyongyang may have sent engineers to operate North Korean missiles sold to Russia. This could pose a threat to South Korea, as the North could strengthen its weapons capabilities based on evaluations of battlefield use.

In recent weeks, Ukrainian reports have suggested that North Korean troops are participating in the conflict. These reports claim that Russia is forming battalions that include North Korean soldiers and that some of them were killed in missile attacks on the Ukrainian battlefield. Other reports suggest Pyongyang already sent as many as 10,000 troops to support Moscow.

"These are (North Korean) workers for Russian factories to replace Russians killed in the war, and personnel for the Russian army. In fact, this is the participation of a second state in the war against Ukraine on the side of Russia," Ukrainian President Volodymyr Zelenskyy said in a parliamentary speech, Wednesday (local time), backing these reports.

In response, Russia, which has consistently denied any weapons trade with North Korea, rejected these speculations.

“Who is involved in the special military operation is none of their (Ukraine) concern," Russia's foreign ministry spokesperson Maria Zakharova said during a briefing. The term “special military operation” is used by the Russian government to describe its invasion of Ukraine.

Experts who spoke with The Korea Times downplayed the likelihood of North Korea sending a large number of troops to the Ukrainian battlefield. Pyongyang has been forming a closer military alliance with the Kremlin, but deploying combat-ready forces entails big risks for the secretive regime, they said.

“While it is clear there has been weapons trade between North Korea and Russia, sending troops is another matter. If any personnel were sent, they are more likely to be laborers or engineers rather than skilled military forces capable of combat,” Yang Moo-jin, president of the University of North Korean Studies, said.

This photo shows parts of an unidentified missile, which Ukrainian authorities believe to be made in North Korea and was used in a strike in Kharkiv, Ukraine, Jan. 6. Reuters-Yonhap

Yang suggested these engineers could be deployed alongside Russian ground troops to assess the capabilities of North Korean missiles and artillery used in the conflict. This data could later be used to improve North Korea's weapons, he said, potentially posing a threat to South Korea.

A military agreement signed by North Korean leader Kim Jong-un and Russian President Vladimir Putin in June has fueled speculation about troop deployments, but Yang pointed out that the agreement has yet to fully take effect in either country.

Putin submitted a bill to Russia's lower legislative house, Monday, for the ratification of the military treaty, while North Korea has not disclosed its own approval process.

"Technically speaking, formal ratification is required to send troops. Without this process, such actions could have legal consequences under both international and domestic laws,” he said.

Cho Han-bum, a senior researcher at the Korea Institute for National Unification, voiced a similar view.

“There is a low possibility — nearly zero — that North Korea has sent thousands of combat-ready troops. Participating in the Ukraine war would mean fighting NATO, and the Kim Jong-un regime would not want a direct conflict with the U.S.-led military alliance," Cho said.

The researcher, citing several sources in Russia, suggested that while there has been some involvement of North Korean personnel in the Ukraine war since last year, they were mostly laborers or engineers rather than combat forces.

He also noted that the Kim regime, which recently stated that inter-Korean relations are nearing a state of war, would not risk sending its forces abroad at this time, where they are likely to be seriously injured or killed.

North Korean leader Kim Jong-un, left, and Russian President Vladimir Putin smile during their meeting in Pyongyang, June 19. AP-Yonhap

Another expert on North Korea, speaking on condition of anonymity, said, “I think it's too early to draw conclusions since Ukraine has not yet presented clear evidence of North Korean troops. However, these claims that North Korea has begun to deploy military personnel, in addition to the weapons it has been providing, could be used as leverage by Kyiv to increase pressure on South Korea for weapons support."

Since the war began in February 2022, Seoul has maintained a policy of providing only financial and humanitarian aid to the war-torn nation, wary of impacting relations with Moscow. Ukraine and Western nations have been pressing Seoul to send lethal weapons.

Regarding the potential deployment of North Korean troops, South Korea's National Intelligence Service said it is “looking into the reports, keeping in mind that they could be true."

The Ministry of Unification said Thursday that it did not have relevant information to address the speculation, but is closely monitoring the issue with other government bodies. The foreign ministry said, "We are working to verify the speculation. If the report is true, we consider it tantamount to participation in the war, and thus are taking it very seriously."