Leaked records reportedly reveal a covert Moscow-Tehran effort to develop ramjet technology for hypersonic cruise missiles capable of threatening U.S. warships

Russia has secretly assisted Iran in developing hypersonic cruise-missile technology in what the Financial Times described as “one of the most dramatic transfers of strategic military technology from Moscow to Tehran.” An extensive investigation by the newspaper, based on leaked correspondence, travel documents and an examination of military patents, reportedly uncovered details of the program. The initiative began in 2023 and continued even as the United States and Israel conducted military campaigns against Iran.

According to the investigation, the classified effort, known as Project C430L, brought together specialists to help Iran develop a new weapons capability intended to threaten U.S. aircraft carriers, which have been deployed intermittently in the region as well as other naval vessels operating in the Middle East.

“This is the transfer of highly sensitive strategic military technology the kind the Iranians have been trying to obtain for decades,” said Fabian Hinz, an expert on Iranian missiles and a senior analyst at Conflict Armament Research. “A program like this requires political approval from the highest levels in Russia.”

At the heart of the project is the development of a ramjet propulsion system. Such engines allow cruise missiles to travel at several times the speed of sound. By combining extreme speed with low-altitude flight, hypersonic cruise missiles can potentially shorten the window available for air-defense systems to detect, track and intercept them.

Hypersonic missiles generally travel at speeds of at least five times the speed of sound. They can also be highly maneuverable and precise, and some are capable of carrying nuclear warheads. Roughly seven years ago, Russian President Vladimir Putin publicly announced the development of the Kinzhal, or “Dagger,” saying the weapon could strike targets almost anywhere in the world while penetrating U.S. air defenses. Russia has subsequently used the Kinzhal during its war in Ukraine.

The Financial Times reported that Iran has succeeded in developing the propulsion technology involved in the project, although there is currently no evidence that an Iranian hypersonic cruise missile has been deployed operationally. Jim Larson, a former CIA analyst specializing in Iran, said: “This technology would give Iran a strategic weapons system that could threaten U.S. Navy vessels.”

Russian experts reportedly helped Iran overcome technical hurdles

Leaked correspondence reviewed by the newspaper reportedly shows that discussions surrounding the project continued through the summer. While military cooperation between Russia and Iran has been widely documented, C430L is described as evidence of what the report calls a “deeper interaction” because Moscow was not simply providing finished equipment. Instead, Russian assistance reportedly gave Iranian engineers the practical expertise needed to develop the weapons system themselves.

The effort was reportedly coordinated by Rosoboronexport, Russia’s state-owned arms exporter, together with NPO Mash. The United States sanctioned NPO Mash in 2014.

According to the investigation, senior Russian officials and engineers traveled to Iran even before the project’s formal contract was signed in November 2023. Correspondence reportedly shows Russian specialists examining the performance of a system Iran had already developed and providing technical assistance to improve it. In April 2025, a proposal was reportedly made to send a 24-member Russian delegation to Iran for technical consultations connected to the project.

Hinz emphasized the importance of transferring expertise rather than simply providing hardware. “Russia has focused on this technology for a long time. People tend to think cooperation like this means sending blueprints, complete missiles or parts of them, but bringing in a 60-year-old engineer who can fly over and solve problems on the ground is an enormous asset.”

The newspaper reported that cooperation under Project C430L continued into 2026. Neither Iran nor Russia responded to requests for comment regarding the allegations.

Putin and Iran maintain close ties despite U.S. pressure

The revelations come amid continued high-level engagement between Moscow and Tehran. Earlier Tuesday, Putin met Iranian President Masoud Pezeshkian, who thanked the Russian leader for his support and told him: “We appreciate your supportive position. The powers do not have the right to attack other countries and violate international frameworks and laws.” Putin, meanwhile, said Russia would continue its trade relationship with Tehran despite the “military-political situation.”

The developments also follow an unusual visit to Russia by CIA Director John Ratcliffe last week. U.S. media organizations, including The Wall Street Journal and Politico, reported that Ratcliffe traveled to Moscow to warn Russian officials against attacking NATO and against providing further assistance to Iran. Officials cited by Politico said the trip was aimed at persuading Moscow to scale back its economic and military support for Tehran.

Washington presses Moscow as military cooperation deepens

A British official who spoke to the outlet said Ratcliffe raised the issue after U.S. Treasury Secretary Scott Bessent threatened tougher sanctions against countries that continue maintaining economic ties with Iran. According to the official, Ratcliffe made clear that Washington expects Russia to halt the transfer of weapons and defense technology to Iran and urged Moscow not to “overreact” if U.S. sanctions affect Russia.

U.S. reports did not establish whether Ratcliffe held a personal meeting with Putin. President Donald Trump characterized the CIA director’s trip as “semi-routine.” The previous known visit by a CIA director to Russia occurred in November 2021, shortly before Moscow launched its full-scale invasion of Ukraine.

NBC reported last month that Russia was continuing to send shipments of ammunition to Iran through a protected and relatively isolated maritime route across the Caspian Sea. The reported cargo included TNT and components used in drones. Although transfers along the route had previously been documented, the U.S. network reported that the volume of material moving between the two countries was larger than previously understood. The Caspian Sea has long served as an important strategic transportation corridor linking Russia and Iran, in part because the United States has no military presence there.

The latest revelations add to a growing body of reporting about the deepening military and strategic relationship between Moscow and Tehran. Russia has also reportedly provided Iran with satellite imagery and drone technology since the beginning of the war with Israel, along with information about the locations of military targets. The reported assistance was intended to help Tehran target U.S. forces, including warships and aircraft. One official who spoke with The Washington Post at the time described the effort as “a fairly comprehensive effort.”If you want, I can also turn this into a more dramatic geopolitical-news style, a professional Reuters/AP-style version, or a more SEO-focused version with a punchier headline and subheadline.