The US has led Western efforts for the deal, which would have seen Iran reduce the amount of material inside the country that could hypothetically be enriched to much higher levels of 90 percent necessary for a weapon.
Iran was censured last week in an overwhelming vote by the International Atomic Energy Agency (IAEA) over its belated declaration of a small, 3,000-centrifuge facility hidden under a mountain near Qom. Revealed in September, inspectors found it to be in an "advanced" stage of construction.
Iran calls the IAEA decision "illegal," and in reaction on Sunday, Ahmadinejad's cabinet approved 10 new industrial-sized enrichment facilities that would mean a 50-fold increase in capacity to more than half a million spinning centrifuges – a goal that would take decades to achieve if actually pursued.
Ahmadinejad said those plans were "not a bluff," during a televised speech on Tuesday.
Yet analysts say the rapid-fire claims of new programs in recent days belie a nuclear program that has had a rocky history of progress. Instructive are the host of problems Iran has already faced in building its first large-scale enrichment facility at Natanz. Designed for some 50,000 centrifuges, just 8,700 have been installed after nearly a decade.
"Iran would probably need to develop significantly stronger domestic capabilities if it were to come anywhere close to meeting this new goal," says Michael Levi, a fellow at the Council on Foreign Relations in New York who has followed Iran's nuclear program for years.