Russia and Iran build new nuclear plant as inspectors struggle to access key sites
Moscow and Tehran signed a $25 billion deal for the Sirik power station while the IAEA reported it could not verify activities at four Iranian enrichment facilities.
By Beatriz Soto ·
International oversight of Iran’s nuclear program has weakened as Tehran and Moscow deepen their technical ties. The two nations recently finalized a massive new construction project even as the International Atomic Energy Agency reported major gaps in its monitoring capabilities.
The centerpiece of this expansion is the Sirik nuclear power plant. Russia and Iran signed an agreement in September 2025 to build the facility in Hormozgan Province, near the Strait of Hormuz. According to reports from Iran’s state news agency, the deal is valued at $25 billion. The planned units will have a combined capacity of approximately 5 gigawatts. This output exceeds the total capacity of the completed Bushehr complex, which is under 3 gigawatts.
Work continues at the existing Bushehr station on Iran’s southern coast. Rosatom, Russia’s state nuclear corporation, has completed the first reactor there. Two additional units are currently under construction. Rosatom stated that the second unit is more than 60 percent complete and is targeted for operation in 2029. The third unit is also under way. Personnel returned to the site following a temporary evacuation. By October 11, 135 Russian engineering and technical specialists were back at work.
The partnership is framed by a Comprehensive Strategic Partnership Treaty that entered into force in October 2025. The practical details are outlined in an intergovernmental Cooperation Plan for 2024-2026, approved in September 2024. This framework allows Russia to maintain commercial interests and influence in the Middle East. It provides Iran with access to nuclear technology, expertise, and fuel supplies that are otherwise difficult to obtain under Western sanctions.
Analysts suggest the balance of power in the relationship favors Moscow. Nikita Smagin, an analyst at the Carnegie Endowment for International Peace, wrote in November 2025 that the relationship is shifting in Russia’s favor. He noted that Iran is in dire need of investment and that Russia remains one of the few available sources. Dmitry Kovchegin and Arkady Mil-Man of Israel’s Institute for National Security Studies described Moscow’s approach as a calculated balancing strategy in a June analysis. They argued that Russia uses cooperation with Iran to strengthen its position in negotiations with Washington.
The International Atomic Energy Agency highlighted these monitoring challenges in a report published on June 4. The agency conducted an inspection at Bushehr from June 1 to 3. However, it could not carry out inspections at other declared nuclear sites during that reporting period. These sites include four uranium enrichment facilities, which the agency identified as the most sensitive locations. The IAEA said it could not verify the status of nuclear material at these sites. It also could not confirm whether Iran had suspended uranium enrichment, reprocessing of spent reactor fuel, and heavy-water-related activities as required by UN Security Council resolutions.
The expansion of nuclear projects coincides with broader military and economic ties between the two countries. A 2025 analysis by the Center for Naval Analyses found that Russia and Iran expanded military contacts and arms transfers since 2022. The two nations have also pursued new trade agreements and closer links between their banking sectors. Despite these gains, CNA researchers pointed out that competition between the two economies could constrain long-term growth.
Nonproliferation specialists are concerned about transparency. They argue that civilian nuclear cooperation could have consequences beyond electricity generation. Specifically, they point to Iran’s accumulation of uranium enriched to 60 percent. This level is not weapons-grade, but it can be enriched further to around 90 percent. The Arms Control Association stated in June 2025 that enrichment to 60 percent has no civil justification. The group added that it puts Iran in a better position to quickly produce enough weapons-grade material for a bomb.
