The Natanz nuclear facility in Iran mysteriously lost power Sunday in what Iranian officials called an act of sabotage, a development that comes amid new negotiations aimed at salvaging the nuclear deal repudiated by the Trump administration three years ago.

Ali Akbar Salehi, head of Iran’s Atomic Energy Organization, described the blackout as an act of “nuclear terrorism” and said the international community must confront this threat.

“The action this morning against Natanz enrichment site shows the defeat of those who oppose our country’s nuclear and political development and the significant gains of our nuclear industry,” Salehi said, according to the Iranian news media. “The incident shows the failure of those who oppose Iran negotiating for sanctions relief.”

Power was cut across the facility, Behrouz Kamalvandi, a civilian nuclear program spokesperson, told Iranian state television. He said there had been no casualties or damage.

Malek Shariati Niasar, an Iranian lawmaker who serves as a spokesperson for the Parliament’s energy committee, wrote on Twitter that the outage was “very suspicious.” He also raised the possibility of “sabotage and infiltration.”

The blackout came less than year after a mysterious fire ravaged part of the Natanz facility, about 155 miles south of Tehran, the capital. Iranian officials initially played down the effect of the fire but later admitted it had caused extensive damage.


Further raising suspicions, the blackout came a day after Iranian officials lauded the inauguration of new centrifuges housed at a site constructed following the Natanz fire. It was not clear from the announcements Sunday whether those new centrifuges were adversely affected by the power failure.

Suspicion in Iran after such disruptions has often focused on Israel, which has sabotaged the nuclear program in the past and regards Iran as its most potent military adversary. But neither the Israeli military nor the Defense Ministry would comment on the matter Sunday.

Israel welcomed former President Donald Trump’s repudiation of the nuclear deal three years ago, and it has expressed deep concern about President Joe Biden’s intentions to restore it and rescind many of the sanctions Trump imposed on Iran.

The disruption at Natanz comes at a delicate time — barely a week after diplomatic talks about reviving the accord began in Vienna.

While there is no direct dialogue between Iran and the United States at the talks, the other participants in the agreement — Britain, China, France, Germany and Russia, under the chairmanship of the European Union — are engaging in a form of shuttle diplomacy.

One working group is focusing on how to lift economic sanctions imposed by the Trump administration, while another is looking at how Iran can return to the terms that set limits on enriched uranium and the centrifuges needed to produce it.


Iran has said that its nuclear ambitions are peaceful and that while it intends to steadily resume nuclear activities prohibited under the deal, it could easily reverse course if the sanctions were rescinded.

On Saturday, President Hassan Rouhani of Iran celebrated the inauguration of the new Iranian centrifuges that shorten the time needed to enrich uranium, the fuel for nuclear bombs.

But Rouhani also insisted that Iran’s efforts were not intended to produce weapons.

“If the West looks at the morals and beliefs that exist in our country, they will find that they should not be worried and sensitive about our nuclear technology,” Rouhani said in remarks reported by Iran’s Mehr News Agency.

Word of the Natanz outage came as Lloyd Austin, the U.S. defense secretary, was in Israel on Sunday for talks with Prime Minister Benjamin Netanyahu and the country’s defense minister, Benny Gantz.

At the meeting, Gantz said, “We will work closely with our American allies to ensure that any new agreement with Iran will secure the vital interests of the world and the United States, prevent a dangerous arms race in our region and protect the state of Israel.”