The Institute for Science and International Security (ISIS) citing satellite imagery reported apparent construction at Taleghan 2, a former nuclear weapons development facility within Iran's Parchin military complex.
“The imagery, captured between September and November 2025, shows a large cylindrical vessel - approximately 36 meters long and 12 meters in diameter—housed inside a new domed building,” the report said on Tuesday.
"What exactly the object is cannot be completely determined from the satellite imagery alone, however, its shape and metal structure are consistent with previous high-explosive test chambers Iran has built," the report added. "The facility is likely entering an advanced stage of construction."
Taleghan 2 is located near Taleghan 1; both are part of the Parchin military complex, about 20 miles southeast of Tehran.
“Reconstruction began as early as May 2025 and has progressed quickly despite the prior damage,” the report said.
The institute said both Taleghan sites were part of Iran’s AMAD Plan, an alleged covert project aimed at developing nuclear weapons.
The AMAD Plan ran from the late 1990s until 2003, according to the International Atomic Energy Agency (IAEA).
Iran denies the existence of the AMAD Plan, insisting its nuclear program is purely peaceful and that nuclear weapons are forbidden by a religious decree from Supreme Leader Ali Khamenei.
The institute which monitors sites activity satellite imagery, reported last month on Iran’s renewed activity in Taleghan 2 site.
“By June 12, groundwork and foundations had been laid, and by late August, a new arch-roofed structure about 45 by 17 meters was under construction over the temporary cover, with two smaller buildings nearby,” the institute added.
The UN nuclear watchdog said on Wednesday it needs more Iranian cooperation to restore full inspections at sites hit in June’s strikes, warning that verification of enriched uranium stocks is “long overdue.”
