(Bloomberg) -- North Korea denied it sold weapons to Russia in an unusually direct statement, and blasted the US over “rumors” that Kim Jong Un’s regime was aiding Vladimir Putin’s war in Ukraine.

“We have never exported weapons or ammunition to Russia before and we will not plan to export them,” the state’s official Korean Central News Agency reported Thursday, citing an unnamed vice director general in the Defense Ministry’s General Bureau of Equipment. 

“We condemn the US for thoughtlessly circulating the rumor against the DPRK to pursue its base political and military aim, and we warn the US to stop making reckless remarks pulling up the DPRK and to keep its mouth shut,” the official said, referring to the country’s formal name -- the Democratic People’s Republic of Korea. He added North Korea still had the right to make the sale.

Earlier this month, US officials said Russia wants to buy millions of rockets and artillery shells from North Korea to use in its war against Ukraine, the latest sign that international sanctions are forcing Moscow to seek help from the nation’s smaller, impoverished neighbor. The UK then said in a Defence Intelligence report that Russia was “almost certainly increasingly sourcing weaponry” from other sanctioned states like North Korea.

Any shipment would be a violation of United Nations sanctions put in place on both countries for military activities. They would also likely be picked up by spy satellites trained on an 11-mile (17-kilometer) strip of land that connects North Korea and Russia, where a rail link that has been closed since the Covid pandemic emerged would likely be used to transport munitions across the continent, and near to the front in Ukraine.

Neither the US nor its allies have presented evidence that weapons have been sent over the border. Shipments by sea run the risk of interdiction.

“Arms sales are clearly a very sensitive and controversial topic for North Korea, particularly when they concern Russia in the current political situation,” said Rachel Minyoung Lee, a manager at the Vienna-based Open Nuclear Network. 

“Pyongyang likely felt the need to put its foot down,” said Lee, who worked as an analyst for the CIA’s Open Source Enterprise for almost two decades.

North Korea has one of the world’s largest artillery forces and been stockpiling shells for decades. Any weapons sales would mark a reversal in roles between the neighbors, as North Korea for decades relied on weapons from its former benefactor, the Soviet Union. An arms sale however could potentially give Kim’s regime much-needed cash, oil, and perhaps even technology to help with its nuclear weapons program.

But the denial shows North Korea sees more to lose than gain from any sales at the moment. It also probably didn’t want to draw attention to any violations of sanctions during the annual session of the United Nations General Assembly, one of the few international bodies that includes North Korea.

“It seems like North Korea is conscious of how it’s aiding of Russia would be viewed in international community,” said Kang Mi-jin, a North Korean defector who now runs a company in South Korea that watches the economy in her former home. “Elevated sanctions are something that it doesn’t want for sure, given Kim Jong Un vowed for improved quality of lives to his people.”

Kim’s regime stood by Russia during the invasion and is one of the few countries that have recognized the Kremlin-controlled “People’s Republics” in Donetsk and Luhansk in eastern Ukraine. Yet the dispatch on Thursday shows that support doesn’t amount to a blank check, a message in line with those delivered to Putin earlier this month by the leaders of India and China.

US officials said Russia is seeking “millions” and rockets and artillery shells, but experts said shipments would like be in numbers well below that and be of use for weapons where there is interoperability -- those linked to the Soviet era. This wouldn’t likely change the dynamics of Russia’s war but Putin’s forces could continue their onslaught in Ukraine. 

The items probably at the top of President Vladimir Putin’s wishlist would be older artillery shells and rockets that take up space and cost Kim’s regime money to keep in storage, said Cheon Seong-whun, a security strategy secretary under former conservative President Park Geun-hye. 

While North Korea has grabbed global headlines with its tests of ballistic missiles, Russia is probably not looking to acquire these weapons because they little would have impact on the battlefield and be seen as a much more severe sanctions violation, weapons expert Joost Oliemans said.

“And that’s without considering the exorbitant prices North Korea would ask for these systems,” he added.

One problem for transport of artillery shells may be in North Korea, where rail systems haven’t been updated for decades and flooding in recent years has wiped out train tracks. North Korea also operates a different rail gauge than Russia, so any cargo would have to be transferred. When Kim held his first and only summit with Putin in Vladivostok in 2019, his heavily armored train missed its mark on the platform and had to go into reverse to line up with the red carpet.

North Korea has been banned from arms sales overseas for more than 15 years by UN resolutions, which grew after tests of nuclear weapons and long-range ballistic missiles by Kim’s regime in 2017. It still sells arms to the likes of Iran, Syria, and Uganda, according to the US Defense Intelligence Agency.

Any potential sale to Russia “is a serious challenge against the UN sanctions regime,” said Maiko Takeuchi, a former member of a UN Security Panel of Experts set up to monitor North Korea’s activities. With Russia holding a veto on the Security Council, she added, “regional or unilateral sanctions would be the only effective measures to ‘punish’ them.”

(Updates with a write through.)

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