WASHINGTON (CNN) -- Iran's efforts to develop its nuclear program have been stymied by a raft of challenges from international sanctions and set back by the 2010 Stuxnet cyberattack, two new reports from a Washington nuclear think tank conclude.
The reports by former weapons inspector David Albright's Institute for Science and International Security (ISIS) say Iran has been forced to use inferior parts and weaker metals, according to officials the group has spoken to at the International Atomic Energy Agency (IAEA), because sanctions have limited access to needed materials.
"Ten years after the start of construction at the Natanz enrichment site, the probability that Iran will build tens of thousands of centrifuges seems remote based on their faulty performance," one of the reports notes.
"Even with advanced centrifuges, Iran may be blocked by sanctions from building advanced centrifuges in large enough numbers."
The Natanz enrichment site was crippled when a computer virus attacked a portion of the centrifuges. But the ISIS report notes enrichment numbers have rebounded to a higher level than before Stuxnet, after a brief dip.
The IAEA noted in recent reports, however, that not all the centrifuges are necessarily enriching. Albright's report says that the Stuxnet worm may have decreased the lifespan of aging centrifuges, even if they were not broken right away, by forcing them to spin at altered speeds.
However, despite the challenges, based on ISIS assessment of Iran's production of enriched uranium, the report concludes the Iranians have more than enough for the stated goal of providing for its research reactor, and Iran appears on a trajectory "to producing weapons-grade uranium for nuclear weapons."