Iran’s stockpile of uranium grows by third

WASHINGTON – Iran has increased its stockpile of 20 percent enriched uranium by nearly a third since May, U.N. investigators reported Thursday, signaling that Tehran is pushing ahead with nuclear development despite tightening U.S. and European sanctions and the threat of an Israeli military strike.

The International Atomic Energy Agency, the U.N.’s nuclear watchdog agency, also reported that Iran has doubled the number of centrifuges, which are used to enrich uranium, in an underground bunker near the holy city of Qom that experts say has been built to withstand an attack.

The findings add to U.S. and Israeli concerns that the Islamic Republic is fast expanding its enrichment efforts even as it negotiates with world powers seeking to curb the program before Iran can develop the capability to build a nuclear weapon. Iran insists that its nuclear program is for peaceful purposes.

The negotiations, which began last spring, have stalled but have not shut down.

“The fact that they have accelerated their activities seems to suggest that they’re using this period of a diplomatic lull to bring as many facilities and centrifuges online as possible,” said Ray Takeyh, an Iran expert at the nonpartisan Council on Foreign Relations. “That way, when they do (re-enter) negotiations, whenever that is, they can say, ‘What’s here is here. Let’s talk about the future.’ ”

Israeli leaders have warned that Iran is approaching a so-called zone of immunity in which an airstrike wouldn’t sufficiently damage Tehran’s ability to build a nuclear weapon. Israeli Prime Minister Benjamin Netanyahu said Thursday that he will deliver a speech on Iran’s “terror regime” at the U.N. General Assembly next month.

The IAEA report, the outlines of which were first reported last week, found that Iran by mid-August had produced a total of nearly 418 pounds of uranium enriched to 20 percent purity, a level that would allow it to rapidly produce the 80 percent enriched fuel needed for a weapon. That figure marked an increase of 31 percent from mid-May.

Investigators also accused Tehran of continuing to dismantle parts of a large military-industrial facility that some analysts believe had been used to conduct nuclear experiments. Iran has consistently denied inspectors access to Parchin, south of the capital, and told the nuclear agency in a letter this week that allegations of nuclear activity there were “baseless.”

“The IAEA is facing real trouble with Parchin,” said David Albright, a nonproliferation expert and president of the nonprofit Institute for Science and International Security. “Iran has really refused to let them in and appears intent on a complete cleanup before they do. And then it’s too late for the IAEA to find out anything about what went on there.”