Iran Fortifies Nuclear Site as Russia, China Block UN Sanctions Monitoring

New satellite imagery indicates Iran has reinforced tunnel entrances at its deeply buried nuclear-linked site, known as Pickaxe Mountain, near the Natanz nuclear complex. Concurrently, Russia and China vetoed a United States-drafted UN Security Council resolution that aimed to extend the mandate of international monitoring for sanctions on Tehran.

The Institute for Science and International Security reported on Thursday that satellite images from September 11 reveal earthen roadblocks remain in place on roads leading to Pickaxe Mountain’s western tunnel entrances. The institute also noted additional soil placed over one western tunnel portal and a nearby cluster of entrances built in 2007. These enhancements increase the amount of earth protecting the entrances, potentially hardening them against aerial bombardment.

These developments follow recent warnings from President Donald Trump, who has repeatedly threatened to strike the site. "We notice there’s a little activity at Pickaxe," Trump told reporters last week. "I would advise Iran not to get cute because we will have to hit them very hard."

Pickaxe Mountain, located approximately two kilometers from Natanz, features multiple tunnel entrances leading into an underground complex. Construction reportedly began in 2020 after an attack damaged an advanced centrifuge assembly facility at Natanz. Analysts estimate parts of the facility may be buried as deep as 100 meters. Iran maintains that no nuclear activity occurs at the site.

Some analysts suggest the opportunity for a direct strike on Pickaxe Mountain may have passed due to the facility's depth and fortification. However, military options remain available, potentially including blocking tunnel entrances to increase the political cost for Iran, according to Behnam Ben Taleblu, senior director of the Iran program at the Foundation for Defense of Democracies.

Reconstruction at Parchin Complex

In related news, the Institute for Science and International Security reported that Iran is actively reconstructing a facility at the Parchin military complex southeast of Tehran. Satellite imagery from September 13 shows Iran has covered the destroyed hardened facility with a tarp, obscuring ongoing work from observation. Dump trucks, bulldozers, concrete equipment, and cranes have been observed at the site.

This facility, Taleghan 2, was reportedly struck by Israel in October 2024 and again in March 2026. The institute stated that new concrete reinforcement has been added, which could offer increased protection against aerial attacks. Questions persist regarding Tehran's ultimate plans for the Parchin site.

UN Security Council Veto

The military developments occurred as Russia and China vetoed a US-sponsored UN Security Council resolution that would have extended the mandate of the Panel of Experts supporting the 1737 Iran Sanctions Committee. The resolution received 11 votes in favor, with Pakistan and Somalia abstaining.

The panel's role is to investigate alleged sanctions violations and report on their implementation. The veto highlights a division within the Security Council regarding the legality and procedure of restoring UN sanctions on Iran through the "snapback" mechanism. While most Council members assert that the sanctions and monitoring structures were validly revived, Russia and China contest this position.

US Ambassador to the UN Mike Waltz stated on Wednesday that Washington considers the snapback sanctions to be legally in effect and expects all parties to enforce them. He emphasized the importance of the expert panel in identifying and addressing attempts by sanctioned entities to evade restrictions.

Separately, an independent UN fact-finding mission reported that it has reasonable grounds to believe that two US strikes on civilian sites in Iran in February constituted war crimes. The mission also concluded that Iranian authorities committed crimes against humanity during their crackdown on anti-government protests. These findings are investigative and do not constitute judicial judgments.