Russia receives hundreds of Iranian drones to attack Ukraine - White House.

Russia is deepening its defense cooperation with Iran and has received hundreds of one-way attack drones that it is using to strike Ukraine.

That’s according to Reuters, Ukrinform reports.

Citing newly declassified information, the White House said the drones, or Uncrewed Aerial Vehicles (UAVs), were built in Iran, shipped across the Caspian Sea and then used by Russian forces against Ukraine.

"Russia has been using Iranian UAVs in recent weeks to strike Kyiv and terrorize the Ukrainian population, and the Russia-Iran military partnership appears to be deepening," White House spokesman John Kirby said in a statement.

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The official noted that the transfer of the drones was a violation of United Nations rules, and the United States would seek to hold the two countries accountable.

"We will continue to impose sanctions on the actors involved in the transfer of Iranian military equipment to Russia for use in Ukraine," Kirby said.

He said a new U.S. advisory issued on Friday aimed "to help businesses and other governments better understand the risks posed by Iran’s UAV program and the illicit practices Iran uses to procure components for it."

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As Ukrinform reported earlier, Iran provides Russia with materials for the construction of a drone factory in Tatarstan, which will be able to provide the Kremlin with weapons to continue its war of aggression against Ukraine.