Türkiye has decided to freeze the assets of 16 individuals and 15 organizations stated to be linked to Iran’s nuclear program.

The decision, signed by President Recep Tayyip Erdoğan and published in the Official Gazette on October 1, 2025, was based on the relevant resolutions of the United Nations Security Council (UNSC).

The action was taken under Law No. 7262, the “Law on the Prevention of the Financing of the Proliferation of Weapons of Mass Destruction.” The Ministry of Treasury and Finance will be responsible for the implementation of the decision.

The individuals and organizations whose assets have been frozen have the right to apply to the Audit and Cooperation Commission for their appeal to be forwarded to the UNSC.

Meanwhile, there is a disagreement between Western countries and Russia and China regarding the legal validity of the UN sanctions.

Western countries argue that Iran has violated its obligations under the nuclear deal and state that they have initiated the “trigger mechanism” that automatically restores UN sanctions.

In response, Russia and China emphasize that the activation of this mechanism lacks a legal basis, as the US withdrew from the agreement and the European parties failed to fulfill their commitments.

Moscow and Beijing had therefore announced that they do not recognize the interpretation that UN sanctions have been reinstated.

Who is on the list?

The annex to the decision published in the Official Gazette provides a detailed list of scientists, administrators, and critical institutions involved in various stages of Iran’s nuclear program.

The decision orders the freezing of assets of 16 individuals who are stated to have played a direct role in Iran’s nuclear activities.

Prominent among these names are experts working in fields such as uranium enrichment, reactor management, and material procurement.

— Davud Agha-Jani: Head of the Pilot Fuel Enrichment Plant (PFEP) at Natanz.

— Behman Asgarpour: Operational Manager at Arak.

— Seyyed Hossein Hosseini: An official of the Atomic Energy Organization of Iran (AEOI) involved in the heavy water research reactor project at Arak.

— Jafar Mohammadi: Technical advisor to the AEOI and responsible for the production of valves for centrifuges.

— Seyyed Jaber Safdari: Manager of the Natanz Enrichment Facilities.

— Ghasem Soleimani: Director of Uranium Mining Operations at the Saghand Uranium Mine.

The list also includes other senior officials involved in areas such as centrifuge component manufacturing, uranium conversion, and nuclear fuel research.

What are the targeted institutions and organizations?

Under the decision, the assets of 15 institutions and companies that form the main backbone of Iran’s nuclear program have also been frozen.

These organizations include research centers, financial structures, and supplier companies.

— Atomic Energy Organization of Iran: The main governing body of the program.

— Bank Sepah and Bank Sepah International: Stated to provide financial support to Iran’s Aerospace Industries Organization.

— Isfahan Nuclear Fuel Research and Production Center (NFRPC): An AEOI unit involved in enrichment-related activities.

— Kavoshyar Company: An AEOI subsidiary said to have attempted to procure vacuum induction furnaces and laboratory equipment for the nuclear program.

— Novin Energy Company: A company operating within the AEOI, stated to have transferred funds to organizations linked to the nuclear program.

— Tamas Company: An umbrella organization responsible for uranium extraction, enrichment, and processing activities.

The list also includes other critically important companies, such as Mesbah Energy Company, a supplier for the heavy water reactor at Arak, and Pars Trash Company, which is stated to be involved in the centrifuge program.

What is the trigger mechanism? How did the process unfold?

The Joint Comprehensive Plan of Action (JCPOA), signed in 2015 between Iran and the P5+1 countries (US, Russia, China, France, the United Kingdom, and Germany), imposed limitations on Tehran’s nuclear program in exchange for the lifting of severe UN sanctions.

This agreement was established on an international legal footing with UNSC Resolution 2231, adopted the same year.

The resolution included not only the lifting of sanctions but also a special provision known as “snapback.” This provision, referred to as the “trigger mechanism,” served as a safeguard, allowing for the reinstatement of all lifted UN sanctions if Iran seriously violated its obligations under the deal.

The mechanism was designed to bypass the veto power of permanent members in the Security Council. Under normal circumstances, a new vote in the Council is required to pass a sanctions resolution, and it must not be vetoed by any permanent member.

However, the snapback provision reverses the process: when one of the parties notifies that Iran is not fulfilling its obligations, the sanctions automatically return within 30 days unless a resolution to the contrary is adopted. This means that a veto from any country cannot stop the process.

Additionally, Resolution 2231 had limited the timeframe for using this right. The deadline to trigger the mechanism was October 18, 2025. After this date, the snapback option would cease to exist.

The crisis, which began with the unilateral withdrawal of the US administration under President Donald Trump from the agreement in 2018, deepened in the following years. Citing Washington’s sanctions, Iran began to increase its enriched uranium stockpiles and use advanced centrifuges.

In the summer of this year, Israel’s attacks on Iran’s nuclear facilities were followed by Tehran’s announcements of retaliation. During the same period, allegations that Iran was limiting its cooperation with the IAEA raised concerns in Western capitals. In response to this situation, Europe’s three major powers—France, Germany, and the United Kingdom (E3)—decided to activate the snapback mechanism.

On August 28, 2025, the governments of London, Paris, and Berlin submitted an official notification to the UN Security Council, announcing that Iran was in “significant non-performance” of its commitments under the agreement. This notification was the step that activated the trigger mechanism.

The notification initiated a 30-day process. If the Council did not pass a resolution to prevent the re-imposition of sanctions within this period, the old sanctions would automatically come back into effect. However, the likelihood of such a resolution passing in the Council was slim from the outset. Since any permanent member could block the resolution by withholding its approval, the path was clear for an automatic snapback.

By mid-September, no resolution to block the snapback had emerged from the Security Council. Consequently, around September 17, all previously lifted UN sanctions were automatically reinstated. The arms embargo, the ban on nuclear technology transfers, and travel restrictions and asset freezes on specific individuals and entities were reactivated.

The European Union also supported this step with a decision on September 29, re-implementing additional sanctions at its own level. Thus, Iran entered a new era of intensified international isolation.

Reactions from Iran, Russia, and China

The Tehran administration declared the process “legally invalid.” The Iranian Foreign Ministry described the E3’s initiative as “political and arbitrary.”

Officials argued that the mechanism was being misused and that the parties failing to fulfill their primary obligations were the US and Europe. They also showed resistance to the pressure by implying that they might restrict cooperation on IAEA inspections.

The snapback process also sparked debate in the international arena. Russia and China reacted strongly to the E3’s move.

Both countries attempted to have the snapback postponed in the Security Council. However, due to the structure of the mechanism, these efforts were unsuccessful. When the deadline expired, the sanctions automatically came into effect. Nevertheless, Russia and China announced that they do not recognize these sanctions.