Ukrainian forces described a different kind of enemy, fighting with unfamiliar tactics and little option to retreat.

Russia signed a strategic partnership treaty with Iran on Friday that follows similar pacts with China and North Korea. All three countries are adversaries of the United States, and Russia has used its ties with them to help blunt the impact of Western sanctions and boost its war effort in Ukraine.

There is mounting evidence from the battlefield, intelligence reports and testimonies of defectors that some North Korean soldiers are resorting to extreme measures as they support Russia's three-year war with Ukraine.

North Korea will send Russia another 150 short-range ballistic missiles this year. Pyongyang is also likely to transfer additional howitzers, as the head of Ukraine's intelligence, Kyrylo Budanov, said in an interview with The War Zone.

North Korea is expected to send reinforcements to Russia’s Kursk Oblast, mainly gun and rocket artillery units, Ukraine’s military intelligence chief Kyrylo Budanov said in an interview with The War Zone magazine published on Jan.

Kyrylo Budanov, head of Ukraine’s Main Intelligence Directorate, said North Korea’s assistance will bolster Russia’s long-range fire capabilities in Kursk Oblast and on the Ukrainian front, but he does not expect many new ground combat units.