Pickaxe Mountain and the Next Iran Nuclear Deal: What Trump Must Demand
- Dan Feferman
- Jul 23
- 5 min read
President Donald Trump says the United States may soon strike Iran’s deeply buried Pickaxe Mountain complex. Whether or not that attack occurs, the facility has already exposed the central challenge confronting any future Iran nuclear deal: How can an agreement stop a nuclear program designed to be hidden deep inside a mountain?
By Dan Feferman
The United States and Iran are currently fighting over freedom of navigation through the Strait of Hormuz, making diplomacy appear remote. But the conflict will eventually end, for now at least. When negotiations resume, Washington cannot simply revive the framework of the 2015 JCPOA nuclear agreement, rather it must address the possibility that Iran is moving critical nuclear infrastructure beyond the reach of inspectors—and perhaps beyond the reach of conventional military force.
Nothing illustrates that danger more clearly than Pickaxe Mountain.
What is Pickaxe Mountain and What Is Hidden Inside?
The Wall Street Journal reported this week that Israeli intelligence believes Iran transferred thousands of uranium-enrichment centrifuges into tunnels beneath Pickaxe Mountain last fall. According to Israeli and American officials, the transfer occurred after U.S. and Israeli strikes severely damaged Iran’s principal nuclear facilities during the June 2025 war.
Pickaxe Mountain—also known as Mount Kolang Gaz-La—is located south of the Natanz nuclear complex. Its tunnels are believed to extend between 300 and 450 feet beneath the mountain, potentially placing portions of the facility beyond the reach of even America’s largest bunker-busting bombs.
The precise purpose of the complex has never been established. Iran previously described it as a future centrifuge-assembly facility, but it has not granted the International Atomic Energy Agency access to the site.
David Albright and the Institute for Science and International Security have assessed that the underground complex is large enough to accommodate far more than centrifuge production. It could potentially house an enrichment plant capable of producing weapons-grade uranium, as well as activities associated with converting that uranium into nuclear-weapons components.
There is no publicly available evidence that Iran is currently enriching uranium inside Pickaxe Mountain. Centrifuges would still have to be installed in cascades, supplied with uranium feedstock and connected to the necessary power and support systems. But the reported transfer is nevertheless alarming. If Iran has placed thousands of centrifuges inside an inaccessible mountain, it may be preserving the foundation of a future covert enrichment program—one designed to survive both international scrutiny and military attack.
The Israeli assessment has not been independently confirmed in public. Indeed, recent satellite analysis found no visible evidence that Iran had resumed enrichment and concluded that its centrifuge program remained badly damaged. But satellite imagery cannot show what has been moved into underground halls. That uncertainty—not proof of an operating enrichment plant—is precisely what makes Pickaxe Mountain so dangerous.
The Central Weakness of the 2015 JCPOA Iran Nuclear Deal
The original Iran nuclear agreement, formally known as the Joint Comprehensive Plan of Action, imposed meaningful restrictions on Iran’s program. It limited enrichment to 3.67 percent (civilian grade), capped Iran’s enriched-uranium stockpile and restricted the number and types of centrifuges Tehran could operate.
Its fundamental weakness was that many of its most important restrictions were temporary. The limits on Iran’s operating centrifuges began to loosen after ten years. The restrictions on enrichment levels and uranium stockpiles were scheduled to expire after 15 years, around 2030. Iran would still have been prohibited from building a nuclear weapon and remained subject to safeguards obligations. But the JCPOA’s most important numerical limits—including its caps on enrichment level, uranium stockpile and enrichment capacity—would have expired or begun loosening.
Iran could then have expanded its enrichment capacity, deployed more advanced centrifuges and accumulated much larger quantities of enriched uranium without necessarily violating the agreement. President Trump withdrew the United States from the JCPOA in 2018, arguing that its sunset clauses postponed the Iranian nuclear threat rather than permanently resolving it.
Pickaxe Mountain demonstrates why that criticism remains relevant. A country can technically comply with temporary restrictions while constructing the infrastructure it will need once those restrictions expire. If that infrastructure is buried inside an inaccessible mountain, the international community could eventually face an Iran with an industrial-scale enrichment program, a drastically shortened breakout timeline and far fewer options for stopping it.
Nuclear Breakout Capacity Is Not the Same as Building a Bomb
This distinction must be stated accurately. Nuclear breakout refers to the amount of time required to produce enough weapons-grade uranium for one nuclear weapon. It does not include all the additional steps necessary to design, assemble and deploy a functioning nuclear device.
Before the June 2025 war, Iran had accumulated more than 400 kilograms of uranium enriched to 60 percent, according to the IAEA. That is far beyond what is required for a normal civilian nuclear program and only a relatively short technical step from weapons-grade enrichment.
Iran’s advanced stockpile therefore placed it within weeks—and potentially less—of producing enough weapons-grade material for several bombs if Tehran made the political decision to do so. The time required to transform that material into operational weapons would have been longer and remains uncertain.
Nevertheless, once breakout time is reduced to weeks or days, inspections alone are no longer sufficient. Inspectors might detect a violation, but the international community could lack the time needed to verify it, reach a political consensus and act before Iran produced the necessary material.
What a Future Iran Nuclear Deal Must Include
Any future agreement must permanently prevent Iran from developing an industrial enrichment capability that can be converted rapidly into a weapons program.
First, there should be no sunset clauses on the agreement’s core enrichment restrictions. The limitations must remain in place for as long as the Islamic Republic presents a nuclear-proliferation threat.
Second, if Iran is permitted to enrich uranium at all, enrichment should be permanently capped at 3.67 percent, with strict limits on its uranium stockpile, centrifuge numbers and use of advanced centrifuges. Any uranium exceeding the permitted stockpile should be exported or rendered unusable. All enrichment should take place at declared, accessible facilities under continuous IAEA monitoring. Underground enrichment, centrifuge production and nuclear-material storage should be prohibited.
Third, Iran must provide a complete accounting of its remaining enriched uranium, centrifuges and nuclear equipment. The IAEA has repeatedly warned that its loss of access has prevented it from verifying the status of Iran’s previously declared nuclear material and facilities. There can be no credible agreement until the missing material and equipment are located.
Iran has still not provided the IAEA with a complete account of the nuclear facilities and materials affected by the June 2025 attacks. Without access, inspectors cannot verify the location, quantity, chemical form or enrichment level of Iran’s remaining uranium—or establish a reliable inventory of its centrifuges.
Fourth, Pickaxe Mountain must be opened to inspectors. Iran should be required to disclose the facility’s complete design, permit unrestricted IAEA access and remove any centrifuges or nuclear-related equipment stored there. The complex should then be permanently barred from enrichment, centrifuge production, nuclear-material storage or weaponization-related activity.
Finally, the agreement must guarantee rapid access to suspicious undeclared locations—including military sites—and impose automatic consequences if Iran delays inspections or obstructs verification.
The Standard for a New Successful Iran Nuclear Deal
The test of any future agreement is not whether it postpones the crisis, but whether it closes every credible pathway to an Iranian nuclear weapon. That means permanent enrichment limits, a full accounting of Iran’s uranium and centrifuges, rapid access to undeclared sites and enforceable consequences for obstruction.
Pickaxe Mountain is the test case. A nuclear agreement that cannot reach inside it will not eliminate Iran’s nuclear threat. It will merely encourage Tehran to move the most dangerous parts of its program deeper underground.
Dan Feferman is the co-founder and co-editor of MiddleEast24 and the editor of MidEastJournal. He was previously a senior intelligence analyst and policy planner in the Israel Defense Forces and has written extensively on Iran’s nuclear program and various Middle East intelligence and defense matters.