SEOUL, South Korea (AP) — South Korea’s president on Thursday raised the possibility of supplying Ukraine with weapons, while emphasizing that his government “will not sit idle” while North Korea reportedly sends troops in support Russian aggression towards its neighbor.

South Korean President Yoon Suk Yeol spoke to reporters after a meeting with Polish President Andrzej Duda, which came a day after U.S. and South Korean officials said they believe about 3,000 North Korean troops have been sent to Russia and trains at multiple locations. South Korea’s spy agency told lawmakers that North Korea is likely to send a total of 10,000 troops to Russia by the end of the year.

Yoon’s meeting with Duda was aimed at expanding defense cooperation between the countries amid the ongoing conflict. Poland has signed a series arms trade with South Korea over the past two years to purchase tanks, howitzers and rocket launchers in an effort to boost its military capabilities following Russia’s invasion of Ukraine.

Both Moscow and Pyongyang have denied the presence of North Korean troops.

Yoon said South Korea will work with allies and partners to prepare countermeasures that could be rolled out in phases depending on the level of military cooperation between Pyongyang and Moscow.

Seoul’s moves could include sending weapons to Ukraine, which would mark a break from a long-standing policy of not supplying weapons to countries actively involved in conflict, Yoon said. He said North Korea’s alleged deployment of troops to Russia is a “provocation that threatens global security beyond the Korean Peninsula and Europe.”

“If North Korea sends special forces to the war in Ukraine as part of Russia-North Korea cooperation, we will support Ukraine in phases and also assess and implement measures necessary for security on the Korean Peninsula,” Yoon said during a joint press conference with Duda. .

“While we stick to our principle of not directly supplying lethal weapons, we may also revise our position more flexibly depending on the level of North Korean military activities,” Yoon said.

Yoon’s comments were consistent with what a senior presidential official told reporters earlier this week, speaking on condition of anonymity. That official said South Korea is considering various diplomatic, economic and military options, including supplying both defensive and offensive weapons systems to Ukraine.

South Korea, a growing arms exporter, has provided humanitarian aid, among other things non-lethal aid to Ukraine and joined US-led economic sanctions against Moscow. So far, the country has resisted calls from Kiev and NATO to supply Ukraine with weapons directly.

During their summit, Yoon and Duda agreed to “actively support” additional deliveries of South Korean military equipment to Poland, including a new deal for Korean K-2 tanks that the governments hope to finalize within this year, according to Yoon’s office.

Tensions on the Korean Peninsula have worsened since 2022 after North Korean leader Kim Jong Un used Russia’s invasion of Ukraine as a distraction to accelerate the growth of his nuclear weapons and missile programs.

Seoul is also concerned as experts say the North could demand major technology transfers in return for sending troops, including Russian expertise in intercontinental ballistic missiles and submarines that would increase the threat from Kim’s nuclear arsenal.

Experts say it is unclear how effective North Korean soldiers would be in combat, given their lack of active battlefield experience, outdated conventional weapons and training experience with Russian forces. Kim could see the troop deployment as a crucial opportunity to expose his soldiers to modern warfare and technologies, said Hong Min, an analyst at the Korea Institute for National Unification in Seoul.

At a parliamentary hearing, South Korean Defense Minister Kim Yong Hyun said North Korean troops would likely become “cannon fodder” if they were deployed in battle in Ukraine. He criticized Pyongyang’s leadership for “selling out its forces to an illegal invasion.”

“Deploying troops is just an expression, and it would be more appropriate to call them mercenaries,” he said. “The North Koreans disguise themselves in Russian uniforms and operate under Russian control, without operational autonomy, and simply follow orders.”