Russia And Iran Expand Nuclear Cooperation As International Oversight Weakens

Russia and Iran are expanding their nuclear cooperation as both countries face Western sanctions and international isolation. Their partnership includes the construction of nuclear power plants, fuel supplies, and broader technological cooperation.

While Bushehr, Iran’s first operating nuclear power station, has long been the centerpiece of their relationship, Moscow and Tehran are planning new nuclear facilities and cooperation in other areas of technology, raising questions about the ability of international agencies to monitor Iran’s nuclear activities.

Russia’s state nuclear corporation Rosatom has played a key role in completing and operating Bushehr, on Iran’s southern coast. A contract to complete the plant’s first reactor was signed in 1995, but the unit did not begin full commercial electricity generation until 2013.

Rosatom has continued work at the site despite the military escalation in the Middle East. After the start of the US-Iran war in February, Rosatom evacuated most of its workers from Iran. But many of the personnel have since returned; by October 11, the Russian nuclear body reported that 135 engineering and technical specialists were back working at the site.

Construction is also continuing on two additional reactor units at Bushehr. Work on a second unit has progressed beyond 60 percent completion, with a target of starting operations in 2029, while construction of a third unit is also under way, according to Rosatom.

Who Benefits Most From The Cooperation?

The Bushehr plant has taken on broader strategic significance as Moscow and Tehran deepen their relationship. The legal foundation of this cooperation is the two countries' Comprehensive Strategic Partnership Treaty, which officially entered into force in October 2025. The practical road map, however, is the intergovernmental Cooperation Plan For 2024–2026, which was approved in September 2024.

For Russia, the nuclear partnership provides commercial opportunities and a way to maintain influence in the Middle East. For Iran, Russian assistance offers access to nuclear technology, expertise, and fuel supplies.

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The benefits are not necessarily equal, though. In a November 2025 article for the Carnegie Endowment for International Peace, analyst Nikita Smagin wrote that “the balance in the relationship is once again shifting in Russia’s favor."

Iran is in dire need of investment, and "Russia remains one of the few available sources," Smagin wrote.

Analysts at Israel’s Institute for National Security Studies (INSS) have argued that Russia increasingly views cooperation with Iran as a way to strengthen its position in negotiations with Washington. In a June analysis, INSS researchers Dmitry Kovchegin and Arkady Mil-Man described Moscow’s policy toward Iran’s nuclear program as a “calculated balancing strategy.”

"[Russia's policy comprises] rhetorical condemnation of military escalation, particularly strikes against nuclear facilities; the provision of limited assistance that does not affect the balance of power between the parties to the conflict; and the offering of mediation services, while seeking to improve its relations with the United States," the authors wrote.

New Nuclear Power Plant

The nuclear partnership is not limited to Bushehr.

In September 2025, Russia and Iran signed an agreement for the construction of a new nuclear power plant, Sirik, in Iran’s southern Hormozgan Province, near the Strait of Hormuz.

Iran’s state news agency, IRNA, reported that the deal was worth $25 billion and that the units would have a combined capacity of about 5 gigawatts. (By comparison, the finished Bushehr complex would have a capacity of under 3 gigawatts.) If completed, Sirik would further tie Iran’s civilian nuclear energy sector to Russian technology and fuel supplies for decades.

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Russia and Iran have strengthened their political, economic and military ties in recent years, with Western sanctions encouraging both countries to develop alternative channels for trade and technological cooperation.

A 2025 analysis by the US-based Center for Naval Analyses (CNA) found that Russia and Iran had expanded military contacts, arms transfers, and technical cooperation since Russia’s 2022 invasion of Ukraine.

The two countries have also pursued new trade agreements, closer links between their banking sectors, increased cross-border trade, and investment in strategic sectors. However, the CNA researchers pointed out that competition between the two economies could constrain the longer-term growth of their economic relationship.

Monitoring Concerns

This burgeoning Russian-Iranian cooperation, especially in the nuclear sphere, comes as the International Atomic Energy Agency (IAEA) faces major obstacles in monitoring Iran’s nuclear activities.

In a report published on June 4, the agency said it had conducted an inspection at Bushehr on June 1–3 but had not been able to carry out inspections during the reporting period at other declared nuclear sites, the most sensitive of which are four uranium enrichment facilities.

The IAEA also said it could not verify the status of nuclear material at those sites or confirm whether Iran had suspended uranium enrichment, reprocessing of spent reactor fuel, and heavy-water-related activities -- processes that can support the production of nuclear weapons -- as required by relevant UN Security Council and IAEA resolutions.

The report highlighted a significant gap in international oversight, but its findings describe the situation during the reporting period and should not be taken as a real-time assessment of access to Iranian facilities today.

Russia faces extensive Western sanctions imposed after its full-scale invasion of Ukraine in February 2022.

The measures target key sectors of its economy, including energy, finance, trade, and defense, and are intended to limit Moscow’s ability to finance the war and access technology used by its military. Russia has also faced sanctions over human rights abuses and actions viewed by Western governments as threats to international security.

Iran has faced decades of US and international sanctions over its nuclear program, concerns about possible nuclear weapons development, and its support for armed groups across the Middle East.

Additional restrictions target Iran’s ballistic missile program, military activities, and human rights abuses. Sanctions were tightened further in recent years amid growing concerns over Iran’s nuclear activities and its military cooperation with Russia, including Tehran's supply of drones used in Russia’s war against Ukraine.

The expansion of nuclear projects alongside reduced international oversight has prompted concerns among nonproliferation specialists about transparency and the potential for sensitive technologies to be diverted.

Some analysts have argued that Russia’s civilian nuclear cooperation with Iran could have consequences beyond electricity generation, namely Iran’s accumulation of uranium enriched to 60 percent.

Uranium enriched to that level is not weapons-grade, but it can be enriched further to around 90 percent, the level generally associated with nuclear weapons.

In a June 2025 analysis, the US-based Arms Control Association said that enrichment to 60 percent “has no civil justification and puts Iran in a better position to quickly produce enough weapons-grade material for a bomb.”