The report also showed that Iran’s stockpile of 20 percent enriched uranium had risen by about 5 percent to 196kg since August, largely due to a temporary halt in converting the material into reactor fuel.
However, it still remained below the roughly 250kg needed for a bomb if processed further — an amount that Israel has indicated is a “red line” that may trigger military action.
Iran says it needs higher-grade enriched uranium to fuel a medical research reactor in the capital, Tehran.
It says it is refining uranium for peaceful energy. Yet its refusal so far to scale back its nuclear program and open it up to unfettered IAEA inspections has drawn tough sanctions that have severely damaged its oil-dependent economy.
The IAEA said Iran had installed only four first-generation IR-1 centrifuges — machines used to refine uranium — at its Natanz plant since August, making a total of 15,240. In the previous three-month period, May to August, it put in place an additional 1,800. Not all of the centrifuges are operating.
The report also said Iran had not installed any more advanced centrifuges, which can refine uranium much faster than the IR-1 model and have also fanned concern in the West.