December 20, 2017

TSC IntelBrief: An Emerging Split Between Russia and Iran Over Syria

Major combat is winding down in Syria. The so-called Islamic State faces defeat from forces including a U.S.-led coalition, while Syrian government and Iran-backed militias have recaptured most of the territory lost to other rebel groups in the first years of the country’s civil war.

• Russia’s announced military drawdown from Syria has triggered geopolitical tensions with Iran, which has a separate long-term agenda for the country.

• A Russian troop drawdown, if implemented, will complicate Iran’s efforts to help Syrian President Bashar al-Assad recapture all of the territory lost to rebel forces in the country’s civil war.

• Preserving the Assad dictatorship is a secondary goal for Russia but essential to Iran’s efforts to supply its primary regional ally, Lebanese Hizbollah.

• Both the U.S. and Israel are applying military and political pressure as they work to limit Iran’s influence in Syria.


Major combat is winding down in Syria. The so-called Islamic State faces defeat from forces including a U.S.-led coalition, while Syrian government and Iran-backed militias have recaptured most of the territory lost to other rebel groups in the first years of the country’s civil war.  On December 11, Russian President Vladimir Putin made a surprise visit to the Russian-run Hmeimim air base in Syria, where he announced the withdrawal of a ‘significant’ portion of Moscow’s  approximately 10,000 regular and contract forces in the country.  

Putin’s drawdown announcement represented a Russian ‘mission accomplished’ declaration and signaled, at least where Moscow is concerned, a transition from combat to diplomacy in deciding Syria’s future. It followed talks held by Putin—first with Assad, then with Iranian President Hassan Rouhani and Turkish President Recep Tayyip Erdogan—in the Russian city of Sochi in November.  If implemented, Russia’s shift from a major combat role will cause tensions with Iran, which will have to bear additional burdens as the remaining lead external force boosting Syria’s military. Iran failed to secure Assad’s military position until Russian intervention in 2015, despite Tehran’s introduction of several thousand Islamic Revolutionary Guard Corps – Qods Force (IRGC-QF) advisers, about 7,000 Hizbollah fighters, and tens of thousands of Iraqi and Afghan Shia volunteers into the conflict. Iran still intends to help the Assad regime recapture all of its lost territory, while resisting any settlement that would dilute its authority.  However, even with the war winding down, the presence of so many Iranian-backed Shi’a fighters risks re-energizing what remains of the Sunni rebel forces still active in Syria. 

Putin’s announcement came with the understanding that Russia will retain significant leverage in Syria, even if it withdraws substantial forces.  Renewed rebel pressure on Assad and his backers in Tehran could also serve Russia’s interests by compelling the Syrian leader to compromise with his opposition.  To Moscow, Assad’s leadership position is secondary to Russia’s global role, which in turn implies its maintenance of naval and air bases in Syria over the long term. For Iran, however, Assad’s firm grip on power is an all-but existential issue.  Both the current Assad regime and that of his father, Hafez al-Assad, have allowed Tehran to use Syria as its key conduit to supply Lebanese Hizbollah—the most visible regional outgrowth of Tehran’s 1979 Islamic revolution and its most reliable and loyal proxy. While Iran has publicly advanced various political transition plans for Syria, most experts believe Tehran will not accept a dilution of Assad’s authority that might threaten the vital supply corridor to Hezbollah. Iran’s leaders calculate they cannot rely on an alternative regime to allow Tehran’s allied forces to stay in Syria.  It’s even less likely that a compromise regime in Damascus would permit Tehran to set up the military and missile bases in Syria that Israeli officials insist Iran is building.  Iran’s ongoing extensive presence in Syria is also key to Tehran’s ability to exert leverage against Israel. Opposition to Israel is a core tenet of Iran’s revolutionary ideology. Positioning its forces to retaliate against Israel or pressure the country militarily is a long-held strategic national goal. Continuing to field Iranian and proxy forces in Syria gives Iran the ability to strike at Israel from multiple axes—from the Syria-Israel border as well as the Lebanon-Israel border. 

Iran’s continued extensive role in Syria and steadfast commitment to Bashar al-Assad’s rule significantly complicates U.S.—Russian diplomacy. The Trump administration has called on its international partners to limit Iran’s regional influence, and U.S. officials have asked Russia, specifically, to use its leverage in Syria to reduce Iran’s presence there.  Defense Secretary James Mattis recently indicated that the U.S. will keep some troops in Syria even after the Islamic State has been completely defeated there—a position that signals the U.S. will not cede all of Syria to Iranian influence.  Israel has put more pressure on Putin by declaring it will not accept the presence of Iranian or Iran-backed forces on its Golan Heights border with Syria.  Israeli Prime Minister Benjamin Netanyahu has urged Putin in several meetings to accommodate Israel’s security needs in Syria.  Israel has also backed up those words with a string of military actions, striking Iranian weapons shipments, Hizbollah positions, and purported Iranian bases in Syria well over 100 times in the past two years.  These dynamics have thrown President Putin off balance diplomatically.  The Russian President cannot satisfy two antagonistic camps simultaneously—Iran and Assad on the one hand, and the Trump Administration and its key ally, Israel, on the other.  For Russia, the diplomacy surrounding its Syria exit strategy might prove more of a quagmire than the actual combat.

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