Editor's note: This article has been updated to include President Volodymyr Zelensky's Oct. 14 statements regarding North Korea.
President Volodymyr Zelensky on Oct. 14 said that Russia plans to involve North Korea directly in the full-scale war against Ukraine over the coming months.
Russia's plans for the fall and winter include "the actual involvement of North Korea in the war," Zelensky said, citing Ukrainian military intelligence reports.
The previous day, Zelensky warned of Russia's "increasing alliance" with North Korea, stressing it had moved beyond the supply of just weaponry and was now "actually about transferring people from North Korea to the occupying military forces."
The president's warning followed reports that several North Korean officers had been killed in a Ukrainian missile strike in occupied Ukraine, raising speculation about just how involved Pyongyang currently is in Russia’s full-scale invasion.
"We see an increasing alliance between Russia and regimes like North Korea," said Zelensky, who has previously pointed to Russia’s deepening role within an axis of rogue regimes, including Iran, who are allied against Ukraine and its Western allies.
"This is no longer just about transferring weapons. It is actually about transferring people from North Korea to the occupying military forces."
What do we know for certain?
Very little aside from the stated intentions from Moscow and Pyongyang.
Russian President Vladimir Putin and North Korean leader Kim Jong Un signed a strategic defense agreement between Moscow and Pyongyang on June 19.
As part of the alliance, the North Korean military announced that an engineer unit would join Russian forces on the ground in Donetsk Oblast the following month.
No picture or video evidence has emerged to date that this went ahead, and it is not known if the six North Korean officers reportedly killed were part of this unit.
On Oct. 4, Russian milbloggers reported that North Korean military personnel were visiting the front lines as part of an "exchange of experience" program and were being shown how Moscow's forces prepared defensive positions and assault operation techniques.
In a press briefing on June 25, Pentagon spokesperson Pat Ryder said North Korean troops would become "cannon fodder" if they joined Russian forces on the battlefield in Ukraine.
What are we less certain about?
The reports of six North Korean officers killed in Ukraine have not been confirmed beyond a single intelligence source, though South Korean Defense Minister Kim Yong-Hyun said earlier this month it was likely true.
Zelensky provided no further evidence on Oct. 13, and the Kyiv Independent has been unable to verify the reports.
The Guardian reported on Oct. 10, citing an unnamed source in Ukraine, that there are "dozens of North Koreans behind Russian lines" to assist with the launching of Pyongyang-supplied Kn-23 ballistic missiles.
Lim Eul-chul, a professor at the Institute for Far Eastern Studies in Seoul, told AFP the deployment of North Korean soldiers in Ukraine could be viewed from Pyongyang as an opportunity for its military to learn "how to handle different weapons and gain real-world combat experience."
"This might even be a driving factor behind sending North Korean soldiers — to provide them with diverse experiences and wartime training."
Kremlin spokesperson Dmitry Peskov on Oct. 10 dismissed the reports as "fake news."
A Washington Post (WP) article on Oct. 11 cited a Ukrainian military intelligence official as saying "several thousand" North Korean troops were undergoing training in Russia and could be deployed to Ukraine by the end of the year.
It added that North Korean officers were already on the ground in Ukraine in observation roles, but no units of troops had been reported as of yet.
The Institute for the Study of War (ISW) on Oct. 11 said the deployment of North Korean troops to Ukraine could free up Russian forces to concentrate on priority areas on the front lines.
But it also added that if they are of poor quality, North Korean troops "could also create opportunities for Ukrainian exploitation."
There have also been reports of North Korean military or police personnel traveling to join "reconstruction efforts" in occupied Donbas in early 2023.
What about other areas of cooperation?
Regardless of whether or not North Korean troops are physically in Ukraine, there is plenty of other evidence to demonstrate the ever-deepening military ties between Moscow and Pyongyang.
Isolated on the world stage after the full-scale invasion of Ukraine, and with ammunition stocks running low after more than two-and-a-half years of war, Russia has become increasingly dependent on North Korean-supplied weaponry.
The relationship was solidified in late June, when Russian President Vladimir Putin visited Pyongyang, where he signed the partnership agreement with North Korean leader Kim Jong Un, pledging to provide aid to one another if either was attacked.
In August, South Korea’s Yonhap news agency reported North Korea had sent containers presumably to Russia that could contain more than 6 million artillery shells.
In exchange for the ammunition, Russia reportedly provided North Korea with technology to help it deploy spy satellites as well as tanks and aircraft.
The Times reported earlier this month that half of all the artillery shells used by Russia in Ukraine are supplied by North Korea.
Though a large number of the shells are believed to be faulty, the sheer number being shipped to Moscow's forces are believed to have played a crucial role in Russia's grinding advances in eastern Ukraine, most recently the capture of Vuhledar in Donetsk Oblast earlier this month.
Shin Won-sik, South Korean defense minister, said in June that Pyongyang also sent dozens of ballistic missiles that Moscow's troops fire at Ukraine.
But their reliability has also been questioned. Around half of the North Korean missiles fired at Ukraine by Russia have malfunctioned and exploded in mid-air, Reuters reported on May 7, citing Ukraine's Prosecutor General's Office.