Archive · 2 Sep 2026
Leaked Records Allege Russian Help for Iran’s Supersonic Missiles
A report says Russia may be helping Iran build very fast cruise missiles.
The project is called C430L and reportedly began in 2023.
Russian experts are said to be helping Iran improve a ramjet engine.
A ramjet uses air around a moving missile to help it travel quickly.
The missiles could fly low and fast, making them harder for defenses to detect and stop.
Experts believe they could be used against ships or land targets.
Iran has reportedly built and tested the engine.
However, there is no confirmed evidence that a complete Russian-assisted missile is operating.
The reported cooperation continued during the recent conflict involving Iran, the United States and Israel.
A Financial Times investigation alleges that Russia and Iran began the covert C430L programme in 2023.
The programme reportedly focuses on helping Iran develop ramjet propulsion for supersonic cruise missiles.
Russian specialists allegedly reviewed Iranian flight-test data and advised on fuel systems, combustion, air intakes and nozzles.
Iran has reportedly built and flight-tested the ramjet system, but no complete Russian-assisted missile is confirmed operational.
Leaked records indicate cooperation continued into 2026, although Russia and Iran have not officially confirmed the allegations.
- Who
- Russia and Iran are reportedly involved, including Rosoboronexport, NPO Mashinostroyenia, Russian missile specialists and Iran’s Ministry of Defence and Armed Forces Logistics.
- What
- A covert programme allegedly provides Russian technical assistance for Iran’s ramjet propulsion system and potential supersonic cruise missiles.
- When
- The programme reportedly began in 2023, was formally contracted in November 2023, involved technical exchanges in 2025 and reportedly continued into 2026.
- Where
- The reported technical cooperation involved Russian officials and engineers travelling to Iran; the potential weapons are discussed in relation to the Gulf and Middle East.
- Why
- The reported technology could help Iran develop high-speed, low-altitude missiles that give air and missile defences less time to detect and intercept them.
Reported Strategic Significance
Unconfirmed Claims and Capability
Potential threat to military forces
Reported Strategic Significance
Fabian Hinz said the alleged cooperation involved highly sensitive technology that Iran has sought for decades. Jim Lamson said the resulting system could provide Iran with a new weapon capable of threatening United States Navy vessels.
Unconfirmed Claims and Capability
The reports describe alleged technical assistance and propulsion testing, but provide no evidence that a complete Russian-assisted missile has been deployed or used.
Extent of Russian assistance
Reported Strategic Significance
Leaked travel records and correspondence reportedly show Russian specialists reviewing Iranian test data and advising on technical problems, suggesting cooperation beyond simply transferring designs.
Unconfirmed Claims and Capability
The allegations have not been officially confirmed by Russia or Iran, and it remains unclear whether a proposed later phase of cooperation began.
Regional military impact
Reported Strategic Significance
The reported capability could be significant in the Gulf, where United States and allied forces operate land- and sea-based defences and where anti-ship missiles could threaten warships.
Unconfirmed Claims and Capability
The articles do not establish that Iran currently possesses an operational Russian-assisted supersonic missile, so the immediate military impact remains uncertain.
- Programme
- C430L
- Reported start
- 2023
- Formal agreement
- Reportedly signed with Iran’s Ministry of Defence and Armed Forces Logistics in November 2023
- Core technology
- Ramjet propulsion for sustained supersonic flight
- Reported Russian organisations
- Rosoboronexport and NPO Mashinostroyenia
- Iranian progress
- Iran reportedly built and flight-tested the ramjet propulsion system
- Operational status
- No report confirms that a complete Russian-assisted supersonic cruise missile has entered service
- Evidence cited
- Leaked correspondence, travel records, military-patent analysis and Iranian flight-test data reviewed by the Financial Times
Sources
C430L explained: Know how Russia ‘secretly’ helped Iran develop supersonic cruise missiles
Russia secretly helping Iran build supersonic cruise missiles to target US warships: Report
Russia’s ‘Secret’ Missile Project With Iran Might Change West Asia War’s Fate
Russia Allegedly Helps Tehran Develop Supersonic Cruise Missiles Under Secret C430L Programme Amid Rising US-Iran Tensions
Russia Is Helping Iran Build Missiles That Could Target US Warships: Report
Russia Secretly Helping Iran Develop Supersonic Cruise Missiles: Report
Russia helping Iran develop supersonic missile in covert programme, leaked records reveal: FT report
