Russia is accused of covertly assisting Iran to develop supersonic cruise missiles, including technology aimed at threatening aircraft carriers, according to an investigation cited across multiple reports.

The Financial Times, referenced by both outlets, says the cooperation runs under a programme codenamed “C430L” and is based on alleged internal Russian evidence such as correspondence, travel records and military patents. The reports describe the work as multi-year, beginning in 2023 and continuing into at least 2026, involving Russian state arms exporter Rosoboronexport and other missile-related entities, including NPO Mashinostroyenia. Experts quoted in the reporting say the focus includes ramjet propulsion that would allow cruise missiles to travel several times the speed of sound, potentially at low altitude to reduce detection and interception time.

Both outlets link the allegation to broader Russia–Iran military ties, including Iranian drone support for Russia and accusations by Western officials of Russian assistance to Iran during conflict involving the United States and Israel. While the outlets generally present the claim as based on leaked or uncovered documents, they also note uncertainty about whether the technology has been fully fielded and raise the possibility that the information could be aimed at increasing Western pressure on Moscow and Tehran.