Iran is working on advanced uranium centrifuges at new underground sites being built near its Natanz nuclear plant, Israel's defense minister said on Tuesday, providing figures that appeared to exceed those published by the International Atomic Energy Agency (IAEA).
Centrifuges are used to purify uranium for civilian projects or, at higher levels, to make bomb fuel.
Iranian progress in the field is being watched by world powers trying to resurrect a nuclear deal with Tehran, which denies having military designs.
"Iran is making an effort to complete the manufacturing and installation of 1,000 additional advanced IR6 centrifuges in its nuclear facilities, including new facilities being built at underground sites abutting Natanz," Benny Gantz said in a speech at Reichman University.
According to an IAEA report published on March 3, Iran has installed or is planning to install three IR-6 cascades, totaling about 660 machines.
Last month, IAEA chief Rafael Grossi said Iran had set up a new underground Natanz workshop to make centrifuge parts, an apparent precaution against attacks.
In his remarks, Gantz hinted at Israel's long-standing threat to military action if it believes that diplomacy has failed to ensure its archenemy won't make nuclear weapons.
"The cost of such a future war, which we hope will not happen, can be prevented or reduced" with more challenging negotiations by world powers, he said.
"Iran continues to accumulate irreversible knowledge and experience in the development, research, production, and operation of advanced centrifuges," Gantz was quoted as saying by The Jerusalem Post.
Iran is currently enriching uranium to 60 percent and 20 percent at the Natanz facility, levels it reached after US President Joe Biden, who announced his desire to revive the nuclear deal, took office.
Iran and the United States have conducted indirect negotiations for more than a year, intending to reciprocate the commitments of the 2015 nuclear agreement, which stipulates that the enrichment rate must not exceed 3.67 percent, and Tehran is not allowed to operate advanced centrifuges.
"It [Iran] stands just a few weeks away from accumulating fissile material that will be sufficient for a first bomb, holds 60 kg of enriched material at 60%, produces metallic uranium at the enrichment level of 20%," he added.