The blockade of the Strait of Hormuz has eclipsed global attention on Iran’s nuclear program. After gradually limiting access since February 2021, Tehran has completely locked out the International Atomic Energy Agency (IAEA) from inspecting and monitoring its nuclear activities since June 2025.
IAEA Director General Rafael Grossi testified to the Board of Governors last month (September), admitting that the UN agency has been “completely blind” to Iran’s nuclear program for over a year.
Sans a ceasefire or an agreement, the world remains oblivious to Iran’s pursuit of nuclear enrichment and the fate of the 60% highly enriched uranium (HEU) weighing 440.6 kilograms in the form of uranium hexafluoride besides the net overall enriched uranium stock of 20% and 3.67% amounting to 8,834 kilograms. Though devoid of authentic evidence, most of the strategic community assumes that the enriched uranium was transferred and stored in special containers beneath the Pickaxe Mountain facility (Kuh-e Kolang Gaz La), 2 kilometers from the Natanz complex. Iran has since used the ambiguity for leverage. The subterranean complex, lying over 150 meters deep, was exposed in 2022-23 by an Iranian dissident group and later confirmed with satellite imagery. Iran never shared its details with the IAEA except at the last meeting. Hence, the NPT signatory maintains a nuclear site without duly declaring its existence and opening it for the agency’s oversight. For all practical purposes, the Pickaxe Mountain complex is not under IAEA safeguards, and can therefore enrich uranium to weapons-grade level quietly and securely. The nuclear bomb manufacturing and assembly might be in the same complex. By suspending mandatory cooperation with the IAEA and securing the HEU and low enriched uranium (LEU) from destruction in the war and given Iran’s knowledge of bomb assembly unveiled in the early and mid-2000s, it can potentially manufacture six to eight nuclear bombs.
Iran’s principal nuclear sites, namely the Natanz Pilot Fuel Enrichment Plant (PFEP) complex, the Fordow site, the Esfahan nuclear complex, Lavisan 2 or the Mojdeh site, the new Organization of Defensive Innovation and Research (SPND) headquarters, the TABA/TESA Karaj centrifuge manufacturing site, the IR-40 Arak Heavy Water Reactor and Heavy Water (D20) Production Plant and Sanjarian, were all repeatedly hit and rendered inoperable.
On September 9, 2026, the IAEA Board of Governors voted 23 to 3 to refer Iran to the UN Security Council over nuclear non-compliance. According to the agency’s latest report, it has neither received information from Iran regarding the status of its declared nuclear material or facilities nor had access to conduct in-field verification activities at affected sites.
Before the June 2025 attacks, Iran had deployed an estimated 20,000 to 22,000 centrifuges of various efficiencies. As per Maxar Technologies imagery, an 18-foot-diameter hole over the underground Natanz complex and the destruction of multiple surface buildings were visible. The imagery showed several large craters with blue ash spread over the facility. Multiple tunnel entrances appeared blocked with dirt. Maxar imagery showed extensive building damage at the nuclear research center, with debris remaining visibly scattered across roadways.
By February 2026, Iran had constructed roofs over damaged buildings at Natanz and Isfahan. Reuters also reported on ongoing efforts to “harden and defensively strengthen” tunnel entrances near Natanz.
The new roofs are likely part of an effort to assess the state of its assets after the strikes and conceal its activities from satellite surveillance.
Pickaxe Mountain has not been attacked even once, despite President Trump’s repeated threats and increasing alarmism in political and strategic arenas. Though excavation beneath the facility reportedly began sometime in 2020, the existence of multiple tunnels became public in early 2024. Construction is believed to have gathered pace following the 2025 escalation, according to the Center for Strategic and International Studies’ (CSIS) assessment. Based on satellite imagery, the CSIS concluded that this period“… represented the most activity of this kind since the initial construction of the facility and is indicative of increased utilization of the site.”
Located at the Parchin military complex in the Tehran suburbs, Taleghan 2 was hit by Israel in October 2024 but reconstruction started in May 2025 on what is assumed to be a reinforced structure encased in concrete and covered with earth. After Israel struck it again in March 2026, the Institute for Science and International Security reported renewed repairs to cover the three penetration holes on top of the main hardened facility, followed by a concrete roof or sarcophagus over Taleghan 2 to protect it from future strikes around the facility.
Assuming that Iran would not have transferred the enriched material to a safer location amidst imminent threat would be naive. After every attack on components of its nuclear program, Tehran wasted no time in securing the facilities besides replicating them underground. The perpetual quest for redundancy must be expected with regard to the storage of additional spare or installed centrifuges under Pickaxe Mountain. Taleghan 2 is possibly Iran’s laboratory for explosives testing and an assembly facility for nuclear payload. The conjecture sounds more plausible if read with the occasional statements from Iranian lawmakers on quitting the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and developing Iran’s nuclear deterrent. These two supposedly operational facilities depend on the preservation of HEU and LEU. If Iran could successfully install one more centrifuge cascade under Pickaxe Mountain, the likelihood of enriching the remaining 60% HEU to 90% seems real, besides further refining 20% LEU to higher levels. Or, the Pickaxe facility might just be equipped for uranium storage purposes or, at best, manufacturing centrifuges. Perhaps the quantity of remaining uranium is too small and hard to excavate. There is no definite proof that the HEU and LEU containers were transferred to the Pickaxe complex.
Keeping the Strait of Hormuz closed for maritime traffic does sound like a nuclear option but it is far from it. Faced with Trump’s Operation Economic Outcast, Tehran may soon find it self-defeating. Hence, its real nuclear option lies exactly where it has for decades: in nuclear deterrence. The Islamic Revolutionary Guard Corps (IRGC) has gone too far in attacking its Arab neighbors, Israel and the United States alike, that a lasting thaw sounds too optimistic. It ought to tie its hope to the Taleghan 2 and Pickaxe complexes. Here, the question arises as to how fast Iran can translate its quest into reality. Can the IRGC assemble a couple of nuclear payloads ahead of the impending round of attacks? Time is of the essence, that is!
