Western intelligence officials say Russia has obtained hundreds of Iranian drones capable of being used in its war against Ukraine despite US warnings to Tehran against the move.

It is not officially announced whether Russia has begun flying the drones against Ukrainian targets, but the drones appear to be operational and ready to use, said the officials, who spoke to the Associated Press on condition of anonymity to discuss sensitive intelligence.

The reported shipment marks the latest sign of what appears to be closer military cooperation between the longtime allies, which are also broadening their relations in other sectors such as space programs, aviation and automotive industry. 

It also underscores warnings from critics of the ongoing negotiations with Iran to revive the 2015 nuclear deal that the United States left in 2018. An agreement, which would grant Iran billions of dollars in sanctions relief in return for curbs on its nuclear program, is inching forward.

In mid-August, Iran’s Revolutionary Guard confirmed that it held joint drone exercises with Russia at the Kashan Air Base, adding that Belarus and Armenia were also partaking in the drills.

Earlier in the month, US-based think tank, the Institute for the Study of War quoted advisor to the Ukrainian President’s Office, Oleksiy Arestovych, as saying that Iran handed 46 drones over to Russia and that the Ukrainian government has already noted the use of these drones in combat in Ukraine. 

Late In July, an Iranian lawmaker said military cooperation between Tehran and Moscow has upset the political equations of the global order, confirming Russia’s request to buy Iranian drones.