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Russian President Vladimir Putin on Thursday appeared to confirm that North Korean soldiers had been sent to fight in Russia, as Ukrainian intelligence officials said the troops had arrived in the Kursk region.
Their presence has been an open secret since South Korea’s intelligence service released video footage of North Korean troops training in Russia’s far east.
The soldiers are expected to fight Ukrainian forces who successfully launched an incursion into Russia’s Kursk region in August, in an attempt to blunt the Russian military’s efforts to seize more territory in eastern Ukraine.
South Korean intelligence officials have estimated 12,000 North Korean troops are now in Russia.
Asked about the evidence at a press conference on Thursday, Putin said “We never doubted at all that the North Korean leadership takes our agreements seriously.”
Putin was referring to article 4 of a strategic partnership agreement between Moscow and Pyongyang, signed in June and ratified by Russian lawmakers earlier on Thursday.
Among other things, the treaty includes an ambiguous clause providing for mutual assistance if either country comes under attack.
“As for our relations with the Democratic People’s Republic of Korea, as you know, today I think our strategic partnership agreement has just been ratified. There is article 4 there,” Putin said.
“What and how we will do is our business within the framework of this article,” he added.
The Kremlin initially dismissed reports about North Korean soldiers being dispatched to Russia as “fake news”.
The troops have been disguised as Asian ethnic minorities such as Buryats and Yakuts from Russia’s far east.
Their deployment is the first use of foreign soldiers since Moscow’s full-scale invasion of Ukraine in 2022.
Pyongyang has previously supplied Russia with artillery munitions and other weapons, such as KN-23 ballistic missiles, which were accompanied by North Korean officers sent to oversee their use on the battlefield.
Russia has had difficulty dislodging the Ukrainian troops in the Kursk region since their incursion in the summer.
Ukraine’s military intelligence service said on Thursday: “The first units of the military from the DPRK, which were trained at the eastern Russian training grounds, have already arrived in the combat zone of the Russian-Ukrainian war. In particular, on October 23, 2024, their presence was recorded in the Kursk region.”
The treaty between Russia and North Korea took observers by surprise when it was signed last June, amid speculation about how closely both sides would adhere to the ambitious language.
Article 4 of the treaty states if one of the parties is attacked “the other party will immediately provide military and other assistance with all means at its disposal”.
The treaty provides a few caveats, such as that the assistance must be consistent with the laws of Russia and North Korea.
Western experts were sceptical about Putin’s decision to invoke the treaty. James Nixey, director of the Russia programme at Chatham House, the London-based think-tank, called it “self justifying bluster”.
“The historical evidence shows that Russia is adept at legal sophistry in its attempts to justify its actions,” he said.