Russia needs “significant” ammo supplies from countries other than Iran and North Korea in order to sustain its offensives in Ukraine, a senior NATO official said, per Reuters.

The unnamed official shared NATO intelligence with reporters ahead of the military alliance’s annual summit in Washington, DC.

“To sustain real offensive operations, we think that Russia would have to secure significant ammunition supplies from countries beyond what it is already getting from Iran and from North Korea,” they said, per Reuters.

Russia has turned to allies like North Korea and Iran to replenish its dwindling ammunition stockpiles as its troops launch grinding offensives in Ukraine and burn through artillery shells.

While the total amount of ammo the two countries have sent to Russia is unclear, South Korea’s defense minister said in February that North Korean weapons factories were “operating at full capacity” making arms and ammunition for Russia.

He also said it had sent 6,700 containers to Russia since last August.

Meanwhile, Iran sent 300,000 artillery shells to Russia in 2023, an unnamed NATO official told CNN in March.

Russia has also ramped up its own production.

According to an analysis by consulting firm Bain & Company, reported by Sky News in May, Russia’s armaments industry is expected to make or refurbish 4.5 million artillery shells this year — three times more than Ukrainian allies’ 1.3 million expected shells.

However, even help from Iran and North Korea won’t be enough for Russia to sustain offensive operations on the battlefield in Ukraine, according to the NATO official.

In addition to munition problems, Russia also faces a lack of manpower on the battlefield after its army suffered “very high” losses in Ukraine, the NATO official said, meaning it can’t mount a large-scale offensive.

“Vladimir Putin would have to order a new large-scale mobilization,” the official said, per Reuters, adding that Russia is having to “order undermanned, inexperienced units to move into areas to achieve unrealistic objectives.”