At Iran’s largest nuclear complex, near the city of Natanz, fast-spinning machines called centrifuges churn out enriched uranium. But its output is steadily declining as the equipment ages and breaks down, according to an analysis of data collected by U.N. nuclear officials.

Iran has vowed to replace the older machines with models that are faster and more efficient. Yet new centrifuges recently introduced at Natanz contain parts made from an inferior type of metal that is weaker and more prone to failure, according to a report by the Institute for Science and International Security, a Washington nonprofit group widely regarded for its analysis of nuclear programs…

Albright noted that Iran has behaved erratically in other arenas as well, using novel tactics to try to gain advanced materials and technology for its nuclear program and weapons systems.

“Their procurement efforts are less thought-through, and they’re getting caught a lot more, which suggests that they are becoming more desperate,” he said.