The announcement coincided with talks Wednesday with senior U.N. nuclear inspectors seeking to expand probes into suspected weapons-related tests. It also could add pressure to planned negotiations later this month between Iran and world powers.
The official IRNA news agency quotes Fereidoun Abbasi as saying that Iran began installing the new centrifuges at Natanz site in central Iran about a month ago. He says they only will be used to produce low-level enriched uranium.
But advanced centrifuges can vastly increase Iran's pace of enrichment, which the West fears could be eventually turned into warhead-grade material. Iran insists it wants nuclear fuel only for energy reactors and research.