The new assessment contrasted with U.N. agency view that Iran could resume enriching uranium in a “matter of months.”

Pentagon reports Iran's nuclear facilities were "completely obliterated" in June strikes, offering a more optimistic assessment than earlier estimates while Iran acknowledges damage.

Several experts have cautioned that Iran likely moved a stockpile of near weapons-grade highly enriched uranium out of the deeply buried Fordow site before the strikes and could be hiding it.