Prior to today’s Israeli airstrikes, Washington and Tehran engaged in multiple discussions regarding Iran’s nuclear program, amid rising concerns over its swift expansion.
Israel has conducted extensive strikes against Iran, claiming to target nuclear facilities, ballistic missile production sites, and military leaders.
In recent years, Iran has considerably accelerated its nuclear program, especially after the landmark agreement with global powers aimed at limiting its nuclear activities fell apart in 2018 when the United States withdrew unilaterally.
As of mid-May, the total stockpile of enriched uranium in Iran was estimated at 9,247.6 kilograms—over 45 times the limit established in the 2015 agreement, according to the latest International Atomic Energy Agency (IAEA) report.
Within this stockpile, Iran possesses approximately 408.6 kilograms enriched up to 60%—just a minor step away from the 90% required for a nuclear warhead.
Theoretically, the nation has enough material, if further refined, for around 10 nuclear bombs, as defined by the Vienna-based IAEA.
However, Iran has consistently denied any intentions to develop nuclear weapons.
Below is a list of Iran’s major nuclear sites, which are regularly inspected by the UN nuclear watchdog.
Uranium enrichment plants:
Natanz
Located about 250 km (150 miles) south of Tehran, Natanz is Iran’s heavily fortified main uranium enrichment facility, whose existence was first disclosed in 2002.
Natanz operates nearly 70 cascades of centrifuges across its two enrichment plants, one of which is located underground. A cascade consists of a series of centrifuges—machines essential for the uranium enrichment process.
In April 2021, the site suffered damage from an attack that Iran attributed to Israeli sabotage.
Israeli Prime Minister Benjamin Netanyahu stated that today’s operation struck at the “core of Iran’s nuclear enrichment program,” specifically targeting the Natanz facility and its nuclear scientists.
IAEA Director-General Rafael Grossi confirmed that the Natanz site was “among the targets.”
Fordo
Built secretly in violation of United Nations resolutions under a mountain near the holy city of Qom, Fordo was publicly revealed in 2009.
Initially described as an “emergency” facility constructed underground for protection from potential airstrikes, Iran later indicated it was an enrichment plant capable of housing approximately 3,000 centrifuges.
In 2023, uranium particles enriched up to 83.7% were discovered at the Fordo plant, which Iran claimed resulted from “unintended fluctuations” during enrichment.
Uranium conversion and research reactors:
Isfahan
At the uranium conversion facility in Isfahan, central Iran, raw mined uranium is converted into uranium tetrafluoride (UF4) and then into uranium hexafluoride (UF6), which is a feed gas for centrifuges.
The plant underwent industrial testing in 2004 upon its completion.
The Isfahan center also contains a nuclear fuel fabrication facility, inaugurated in 2009, that produces low-enriched fuel for power plants.
In July 2022, Iran announced plans to construct a new research reactor at this site.
Arak
Construction on the Arak heavy-water research reactor, located on the outskirts of Khondab, began in the 2000s but was halted under the stipulations of the 2015 agreement.
Iran has since informed the IAEA of its plans to commission the reactor by 2026.
The reactor was officially intended to produce plutonium for medical research, and the site includes a heavy water production plant.
Tehran
The Tehran nuclear research center features a reactor supplied by the United States in 1967 for the production of medical radioisotopes.
Nuclear power plants:
Bushehr
Iran’s sole nuclear power plant, located in the southern port city of Bushehr, was constructed by Russia and began operating at a lower capacity in 2011 before being integrated into the national power grid in 2012.
Russia continues to supply nuclear fuel for the plant, which remains under IAEA oversight.
A German company initially began constructing the plant, designed with a nominal capacity of 1,000 megawatts, but construction was halted following the 1979 Islamic Revolution. Moscow later completed the project.
Darkhovin and Sirik
In late 2022, Iran began constructing a 300-megawatt power plant in Darkhovin, located in the southwest. In early 2024, it also commenced work in Sirik, situated in the Strait of Hormuz, on a new complex of four individual plants with a combined capacity of 5,000 megawatts.
