Iran is ringing two deeply buried tunnel complexes with a massive security perimeter linked to its main nuclear facility, a report said Wednesday, amid US and Israeli threats of attack.
The Institute for Science and International Security released its report based on recent satellite imagery as the US and Iran prepare to hold a third round of talks this weekend on a possible deal to reimpose restraints on Tehran's nuclear program.
US President Donald Trump, who pulled the US out of a 2015 pact designed to prevent Tehran from developing nuclear weapons, has threatened to bomb Iran unless a deal is quickly reached that would ensure that same goal.
Trump's withdrawal prompted Iran to breach many of the pact's restraints. Western powers suspect it is pursuing the capability to assemble a nuclear weapon, which Tehran denies.
David Albright, the institute president, said the new perimeter suggested that the tunnel complexes, under construction beneath Mt. Kolang Gaz La for several years, could become operational relatively soon, Reuters reported.
Tehran has not allowed UN nuclear inspectors access to the complexes, Albright said.
That has raised concerns that they could be used to store Iran's stockpile of highly enriched uranium or undeclared nuclear materials, and advanced centrifuges that could quickly purify enough uranium for a bomb, he said.
Iran has said that advanced centrifuges would be assembled in one complex in place of a facility at the nearby Natanz plant, the centerpiece of its nuclear program, destroyed by sabotage in 2020.
The complexes, Albright said, are being built at depths much greater than Iran's deeply buried uranium enrichment facility at Fordow, near the holy city of Qom.
Commercial satellite images taken on March 29 showed hardened entrances to the complexes, high wall panels erected along the verges of a graded road encircling the mountain peak, and excavations for the installation of more panels, the report said.
The north side of the perimeter joins the Natanz plant security ring, it said.
The ongoing construction at the complexes appears to underscore Tehran's rejection of demands that any talks with the US lead to the total dismantlement of its nuclear program, saying it has the right to peaceful nuclear technology.
Israel has not ruled out a strike on Tehran's nuclear facilities in coming months, while Israeli Prime Minister Benjamin Netanyahu insists that any talks must lead to the complete dismantlement of Iran's nuclear program.
Iran's nuclear chief Mohammad Eslami, referring to concerns about the vulnerability of the country’s nuclear program, on Tuesday appeared to refer to projects such as the construction of the new security perimeter around the tunnel complexes.
"Efforts are ongoing" to "expand protective measures" at nuclear facilities, Eslami was quoted by Iranian state media as saying at an event marking the anniversary of the establishment of Iran's Islamic Revolutionary Guard Corps (IRGC).
