Iran reportedly began training Russian forces on Iranian UAV systems in recent weeks, demonstrating the deepening military cooperation between Iran and Russia.
www.understandingwar.org/backgrounder/russia-and-iran-double-down-their-strategic-partnership well worth reading.
Putin may seek to benefit from Iranian leaders’ experience operating under heavy international sanctions and building military systems with devalued currencies and limited access to foreign parts. He is also apparently no longer trying to curb Iran's incursions into Syria.
Iran's leverage with Russia has increased.
A worrying development with Iran, though not as worrying as if China started supporting Russia militarily (not heard anything on the latter so far).
Excerpts from the link:
RUSSIA AND IRAN DOUBLE DOWN ON THEIR STRATEGIC PARTNERSHIP
Aug 11, 2022 - Press ISW
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"Ukraine. Iran is providing weapons and possibly conducting cyberattacks to support the Russian invasion of Ukraine. Iran agreed to provide some of its most sophisticated military drones, such as the Shahed-129 and Shahed-191, to Russia for use in Ukraine. A senior Ukrainian official claimed on August 5 that the Kremlin had received 46 drones thus far, and Western media has indicated that Iran could provide up to 300 total. An unidentified US official claimed on August 9 that Russian personnel are currently in Iran training to use the drones.
[Argh, so many Iranian drones. I did not know Iran is such a leader in making drones. Hope Russian soldiers are rubbish at using them. ]
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Changing Power Dynamics
Iran enjoys a stronger position than it had previously in this partnership. Russia has historically been the dominant party, but Iranian leaders have extracted military concessions from the Kremlin in recent months. Tehran has traditionally sought to purchase military technologies from Moscow rather than the inverse. The Kremlin fielding Iranian drones in Ukraine will showcase these platforms to other potential international buyers, further benefitting Iran. Furthermore, Russia has previously tried to limit Iranian influence in Syria but is now enabling its expansion.
These Russian concessions indicate a shifting power dynamic as Putin seeks economic and military support from a position of growing need. Mounting global isolation and the war in Ukraine are weakening Putin and forcing him to lean on Iran (and other revisionist powers) more heavily. Putin may seek to benefit from Iranian leaders’ experience operating under heavy international sanctions and building military systems with devalued currencies and limited access to foreign parts.
US Policy Implications
Deepening Russo-Iranian ties will almost certainly threaten US and allied interests in Europe, the Middle East, and around the globe. Iranian material support to Russia may help the Kremlin achieve some of its military objectives in Ukraine and eastern Europe. Russian support to Iran’s nascent military space program and air force could improve Iranian targeting and increase the threat it poses to the US and its partners in the Middle East. Growing Iranian control and influence in Syria will enable the IRGC from Syria to threaten US military bases in the Middle East and our regional partners, such as Israel and Turkey, more effectively. Finally, Moscow and Tehran will likely leverage their deepening economic ties to mitigate US sanctions."