Russia is in the process of buying millions of rockets and artillery shells from North Korea for its invasion of Ukraine, according to newly downgraded US intelligence.
A US official, who spoke on the condition of anonymity, said the Russian Ministry of Defence turning to the isolated state of North Korea demonstrates "the Russian military continues to suffer from severe supply shortages in Ukraine, due in part to export controls and sanctions".
US intelligence officials believe the Russians could look to purchase additional North Korean military equipment in the future. The intelligence finding was first reported by The New York Times.
The US official did not detail how much weaponry Russia intends to purchase from North Korea.
The finding comes after the Biden administration recently confirmed the Russian military in August took delivery of Iranian-manufactured drones for use on the battlefield in Ukraine.
The White House said last week that Russia has faced technical problems with Iranian-made drones acquired from Tehran in August for use in its invasion.
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Russia picked up Mohajer-6 and Shahed-series unmanned aerial vehicles (UAVs) over several days last month as part what the Biden administration says is likely part of a Russian plan to acquire hundreds of Iranian UAVs for use in Ukraine.
North Korea has sought to tighten relations with Russia as much of Europe and the West has pulled away, blaming the United States for the Ukraine crisis and decrying the West's "hegemonic policy" as justifying military action by Russia in Ukraine to protect itself.
The North Koreans have hinted interest in sending construction workers to help rebuild Russian-occupied territories in the country's east.
North Korea's ambassador to Moscow recently met with envoys from two Russia-backed separatist territories in the Donbas region of Ukraine and expressed optimism about co-operation in the "field of labour migration", citing his country's easing pandemic border controls.
In July, North Korea became the only nation aside from Russia and Syria to recognise the independence of the territories, Donetsk and Luhansk, further aligning with Russia over the conflict in Ukraine.
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Pyongyang's provocation comes as Washington becomes increasingly concerned about North Korea's accelerated pursuit of nuclear weapons.
North Korea has test-fired more than 30 ballistic missiles this year, including its first flights of intercontinental ballistic missiles since 2017, as leader Kim Jong Un pushes to advance his nuclear arsenal despite US-led pressure and sanctions.
Washington has frequently downgraded and unveiled intelligence findings over the course of the grinding war in Ukraine to highlight plans for Russian misinformation operations or to throw attention on Moscow's difficulties in prosecuting the war. Ukraine's smaller military has put up stiff resistance against the militarily superior Russian forces.
Russian President Vladimir Putin and Mr Kim have recently exchanged letters in which they both called for "comprehensive" and "strategic and tactical" co-operation between the countries.
Moscow has issued statements condemning the revival of large-scale military exercises between the US and South Korea this year, which North Korea views as an invasion rehearsal.