Nuclear centres may be opportunity that Israeli planners will not miss
On Tuesday, Rafael Grossi, the head of the International Atomic Energy Agency, said Iran told him that “all the nuclear complexes that we are inspecting every day would remain closed on security considerations”.
If Israel decides to launch retaliation inside Iran, it could be tempted to combine its long-held objective of slowing Iranian nuclear research – suspected by some analysts as inching towards weapons capability – with striking back.
Mr Grossi, who leads the inspections of Iran’s nuclear programme and verifies if it is intended for civilian use, has said Tehran has enough enriched uranium for several nuclear weapons.
Where are Iran’s main nuclear sites that the UN has inspected, or been obstructed from visiting, and what is the current controversy?
Iran has declared 21 sites to the agency and the organisation has also inspected sites where uranium particles have been found, including some enriched to more than 80 per cent – close to the level required for a nuclear weapon.
The sites are scattered across Iran, but the biggest sites, Natanz and Fordow, are embedded in mountains 225km south of Tehran and 32km north-east of Qom respectively.
Inspections have been intermittent, despite the US, EU and UN insistence on access, mirroring talks on returning to a 2015 deal that former US president Donald Trump abandoned.
The Joint Comprehensive Plan of Action under president Barack Obama briefly allowed UN inspectors access to sites, regulating uranium enrichment for civilian purposes, in exchange for sanctions relief.
However, since its collapse, relations between the agency and Tehran have frayed. Tehran has accused the IAEA of working with Israel to sabotage its nuclear development programme.
In March, the organisation accused Iran of making worrying statements on its “technical capabilities to produce nuclear weapons,” which “only increase the director general’s concerns about the correctness and completeness of Iran’s safeguards declarations”.
The IAEA is still asking Iran to explain undeclared nuclear material at sites in Lavisan-Shian, Varamin, Marivan and Turquzabad.
If Israel decides to hit Iran’s nuclear programme directly, it has options that could range from hitting Iran’s space programme, which some analysts say is cover for producing a nuclear missile, to striking uranium enrichment complexes.
Natanz, Fordow, Arak and Isfahan, are the most wellknown nuclear sites, while another, Parchin, is a research complex said to be critical to Iranian missile technology.
All sites have suffered alleged sabotage attacks or unexplained fires or explosions, although there has been no known attack at Arak, despite Iran’s claims to have foiled one.
Fordow, an enrichment plant, is thought to be the site where nuclear research began in the early 2000s, according to the International Institute for Science and Security.
A hardened structure by 2009, Fordow had at least one concrete tunnel leading into a mountain, and work there accelerated in the early 2010s.
Under the JCPOA, enrichment there was briefly halted, but resumed in 2019 once the action plan collapsed.
Natanz is an overground and underground site.
The overground part of the enrichment site was hit by a large explosion in 2021, reportely prompting accelerated construction underground.
Natanz has four tunnel entrances into the Kuh-e Kolang Gaz La, or Pickaxe Mountain, according to the James Martin Centre for Nonproliferation Studies in Monterey, California.
Both sites are thought to be heavily defended by anti-aircraft systems, and analysts speculate that only the largest bombs designed to penetrate the earth and crush bunkers could damage the complexes.
Israel does not possess such bombs or jets that could carry them, but it does have GBU72s, which could damage hardened structures closer to the surface, and possibly bury or destroy tunnel entrances.