Diplomats say Iran has tripled installations of high-tech machines at its main enrichment facility to more than 600 in three months -- machines that could be used in a nuclear weapons program.
They say the machines are not yet producing enriched uranium and some may be only partially installed. Still the move is the latest sign that 10 years of diplomatic efforts have failed to persuade Tehran to curb its uranium enrichment program.
It also suggests that Iran possesses the technology and the raw materials to mass-produce centrifuges that can enrich much faster than its present centrifuges.
Tehran says it is enriching uranium only for nuclear energy, not weapons.
The two diplomats demanded anonymity Wednesday because they are not authorized to disclose their knowledge of International Atomic Energy Agency inspections.