Russia has secretly helped Iran develop advanced supersonic cruise missile technology capable of threatening US warships and other military targets in the Middle East, the Financial Times (FT) reported on Tuesday, Sept. 1.
The FT said its investigation uncovered a multiyear covert program, codenamed C430L, which began in 2023, and continued into 2026. The program involved Russian missile specialists helping Iran develop a ramjet propulsion system, which can allow cruise missiles to maintain speeds several times faster than sound.
According to the report, the program was arranged by Russia’s state arms exporter Rosoboronexport in cooperation with NPO Mashinostroyenia, a major Russian missile manufacturer. Leaked correspondence reviewed by the FT indicates that Russian engineers travelled repeatedly to Iran and later analyzed data from Iranian flight tests.
“This is the transfer of a highly strategically sensitive military technology from Russia that the Iranians have wanted to acquire for decades,” Fabian Hinz, an expert on Iranian missiles and senior analyst at Conflict Armament Research, told the FT.
Technology that could threaten US warships
Supersonic cruise missiles combine high speed with low-altitude flight, reducing the time available for air-defense systems to detect and intercept them.
The technology could be particularly significant for Iran given the presence of US naval forces and advanced defensive systems in the Gulf.
Iran has already built and flight-tested a ramjet propulsion system, but the FT found no evidence that a Russian-assisted supersonic cruise missile has yet been deployed.
“For the Iranians, this would give them a qualitatively new strategic weapon system that could threaten US Navy vessels,” Jim Lamson, a former CIA military analyst focused on Iran, told the FT.
The leaked documents reportedly show Russian specialists examining the performance of an Iranian propulsion system and questioning Tehran about its fuel system, combustion stability, air intake, and engine nozzle. They also sought clarification about telemetry from an Iranian flight test.
In April 2025, Rosoboronexport proposed sending around two dozen Russian specialists to Iran for technical consultations under the C430L program.
Program continued during war with US and Israel
The reported cooperation continued even after the start of the US-Israeli war against Iran in 2026.
A June 2026 Rosoboronexport letter showed that Moscow and Tehran were still discussing the next stage of the program and Russian technical reports, according to the FT.
The cooperation represents a deeper form of military assistance than simply supplying weapons, with Russia reportedly helping Iran acquire the expertise needed to develop an advanced strategic weapon domestically.
“The secret ramjet program shows Russia is trying to broaden the Ukraine war and draw the US into different theatres,” Nicole Grajewski, a professor at Sciences Po University in Paris, told the FT.
Russia and Iran have already developed close military ties during Moscow’s full-scale war against Ukraine.
Tehran supplied Russia with Shahed attack drones and helped establish their production inside Russia. Western and Ukrainian officials have also accused Moscow of providing Iran with battlefield assistance, including satellite imagery, drone support, and weapons components.
Senior Russian missile specialists involved
The FT identified several senior NPO Mashinostroyenia specialists who travelled to Iran in connection with the program.
Among them was Alexander Dergachev, the company’s chief designer for sea-launched missiles and cruise missile complexes. Along with this, Alexander Chebakov, who headed the company’s air-breathing propulsion design department, reportedly visited Tehran three times in 2023.
Russian patents reviewed by the FT identify Chebakov as an inventor on patents involving supersonic ramjet engines for cruise missiles.
Another specialist, Yuri Prokhorchuk, was reportedly involved in high-speed missile systems and named as an inventor on a patent for a ramjet-powered hypersonic cruise missile designed to strike ships and land targets.
The FT reported that Rosoboronexport’s Vladislav Kuzmichev also travelled to Iran in 2023 and later negotiated the C430L contract with Iran’s Ministry of Defense and Armed Forces Logistics.
Neither the Russian government, Rosoboronexport nor NPO Mashinostroyenia responded to the FT’s requests for comment. The Iranian government also did not respond.
Iran seeks to close a major technological gap
Iran has developed increasingly sophisticated ballistic missiles and produces turbojet and turbofan engines for slower cruise missiles. However, developing a sustained-flight supersonic cruise missile powered by a ramjet has remained a significant technological challenge.
Iran’s efforts to develop the technology date back decades.
In 2016, Iran’s then-defense minister said the country planned to develop supersonic anti-ship missiles. In 2018, two Iranian diplomats were arrested in Ukraine while allegedly attempting to procure components and documentation for the Soviet-era Kh-31A supersonic anti-ship missile.
In 2019, Iran publicly displayed a domestically developed ramjet engine. In August 2023, Iran’s Tasnim news agency reported that the Islamic Revolutionary Guard Corps had begun testing a prototype supersonic cruise missile.
Fabian Hinz said Russian assistance could be particularly valuable because developing a functional ramjet-powered weapon is technically difficult.
“People often think about technology transfers as being solely about sending blueprints, parts, or entire missiles,” Hinz said. “But getting a 60-year-old engineer to fly over and problem-solve, using their experience, is hugely valuable.”
If successful, the program could eventually allow Iran to develop different weapons around the ramjet technology, improve subsequent generations of missiles, and reduce its dependence on foreign suppliers.