Iran’s chief nuclear negotiator, Abbas Araghchi, attends a nuclear deal review meeting in Tehran.

Raheb Homavandi | Reuters

WASHINGTON – Iran will begin 60% enrichment of uranium, a significant step towards weapons-grade materials, in response to an attack on a key nuclear site, the country’s leading nuclear negotiator told state media on Tuesday.

Iranian Deputy Foreign Minister Abbas Araghchi said he had informed the International Atomic Energy Agency, which oversees the surveillance and inspection of nuclear facilities, of Tehran’s decision. It is estimated that 90% of the enriched uranium is needed to develop a bomb.

The move comes two days after Tehran announced that Natanz’s underground nuclear facility has suffered a power outage. The facility in Natanz was previously affected by cyber attacks.

The Iranian Ali Akbar Salehi, the head of the Iranian Atomic Energy Agency, described the event on Sunday as an act of “nuclear terrorism”. A day later, Iran officially accused Israel of being behind the attack and vowed revenge.

Continue reading: Iran calls Natanz nuclear failure blackout “nuclear terrorism”, while the Israeli media point to a cyber attack

The Natanz blackout coincided with the arrival of Defense Secretary Lloyd Austin in Israel to meet with Prime Minister Benjamin Netanyahu and Defense Secretary Benny Gantz.

The Israeli government did not publicly comment on the incident. The White House said Monday the United States was not involved in the attack.

A view of the Natanz uranium enrichment plant 250 km south of the Iranian capital Tehran.

Raheb Homavandi | Reuters

Iran’s decision to increase uranium enrichment comes because the Biden government is working to revive the 2015 Joint Comprehensive Plan of Action (JCPOA) nuclear deal.

The JCPOA brokered by the Obama administration lifted sanctions against Iran, which had paralyzed its economy and cut its oil exports roughly in half. In exchange for billions of dollars in sanction relief, Iran agreed to dismantle part of its nuclear program and open its facilities to wider international inspections.

In addition to the USA, France, Germany, Great Britain, Russia and China were also signatories to the agreement.

In 2018, then-President Donald Trump kept an election promise and unilaterally withdrew the United States from the JCPOA in what was dubbed the “worst deal ever”. Trump also reintroduced the previously lifted sanctions against Tehran.

After Washington withdrew from the landmark nuclear deal, other signatories to the pact struggled to keep the deal alive.