Iranian technicians inspect equipment at an uranium enrichment facility in Isfahan, located 420 km south of the capital Tehran. (Photo: AFP/VNA)

That's an increase of 22.6 kilograms since the IAEA's last report in May.

Uranium enriched up to 60% purity is just a short, technical step away from weapons-grade levels of 90%. By IAEA's definition, around 42 kilograms of uranium enriched to 60% is the amount at which creating one atomic weapon is theoretically possible — if the material is enriched further, to 90%.

IAEA chief, Rafael Mariano Grossi, previously warned that Tehran has enough uranium enriched to near-weapons-grade levels to make "several" nuclear bombs if it chose to do so.

Iran has not commented on the new information, but said its nuclear program has always been intended solely for peaceful civilian purposes.