Russia has established a weapons programme in China to develop and produce long-range attack drones for use in the war against Ukraine, according to two sources from a European intelligence agency and documents reviewed by Reuters.

IEMZ Kupol, a subsidiary of Russian state-owned weapons company Almaz-Antey, has developed and flight-tested a new drone model called Garpiya-3 (G3) in China with the help of local specialists, according to one of the documents, a report that Kupol sent to the Russian defence ministry earlier this year outlining its work.

Kupol told the defence ministry in a subsequent update that it was able to produce drones including the G3 at scale at a factory in China so the weapons can be deployed in the “special military operation” in Ukraine, the term Moscow uses for the war.

Kupol, Almaz-Antey and the Russian defence ministry didn’t respond to requests for comment for this article.

China’s foreign ministry told Reuters it was not aware of such a project, adding that the country had strict control measures on the export of drones, or unmanned aerial vehicles (UAVs).

Fabian Hinz, a research fellow at the International Institute for Strategic Studies, a London-based defence think-tank, said the delivery of UAVs from China to Russia, if confirmed, would be a significant development.

“If you look at what China is known to have delivered so far, it was mostly dual-use goods - it was components, sub-components, that could be used in weapon systems,” he told Reuters. “This is what has been reported so far. But what we haven’t really seen, at least in the open source, are documented transfers of whole weapon systems.”

Still, Samuel Bendett, an adjunct senior fellow at the Center for a New American Security (CNAS), a Washington-based think-tank, said Beijing would be hesitant to open itself up to international sanctions for helping Moscow’s war machine, and that more information was needed to establish that China was playing host to production of Russian military drones.

The US State Department and the Ukrainian government didn’t respond to requests for comment. American officials raised concerns last week about what they said was Chinese support of Russia’s war machine, declining to provide specifics.

The G3 can travel about 2,000 km with a payload of 50 kg, according to the Kupol reports to the ministry. Samples of the G3 and some other drone models made in China have been delivered to Kupol in Russia for further testing, again with the involvement of Chinese experts, they said.

The documents don’t identify the Chinese drone specialists involved in the project that it outlined and Reuters was unable to determine their identity.

Kupol has taken delivery of seven military drones made in China, including two G3s, at its headquarters in the Russian city of Izhevsk, according to the two separate documents reviewed by Reuters, which are invoices sent to Kupol in the summer by a Russian firm that the two European intelligence sources said serves as an intermediary with Chinese suppliers.

The invoices, one of which requests payment in Chinese yuan, don’t specify delivery dates or identify the suppliers in China.

The two intelligence sources said the delivery of the sample drones to Kupol was the first concrete evidence their agency had found of whole UAVs manufactured in China being delivered to Russia since the Ukraine war began in February 2022.

They asked that neither they nor their organisation be identified due to the sensitivity of the information. They also requested certain details related to the documents be withheld, including their precise dates.