The Evolution of Russian and Iranian Cooperation in Syria

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The Russian intervention in September 2015 provided decisive air power to Syrian and Iranian-backed ground forces, expanding Bashar al-Assad’s territorial control and solidifying the regime’s hold on power through parallel diplomatic efforts. Challenges associated with military integration materialized due to the Iranians’ perceived lack of Russian air support and misunderstandings over basing agreements. However, throughout the course of the Syrian Civil War, regularized military and political exchanges strengthened the Russia-Iran relationship while contributing to greater coherence between Moscow and Tehran on the limits and parameters of cooperation. With the changing military dynamics in Syria, Russia, Iran, and Turkey spearheaded the Astana Process as a parallel track to UN mediation. Moscow’s diplomatic and military gains, however, have also embroiled them in the broader regional conflict between the United States, Russia, Israel, and Iran.

Although Russia and Iran have converged around the overarching objective of strengthening the Assad regime, Moscow and Tehran’s engagement in Syria illustrates a complex mosaic of overlapping interests, broader regional entanglements, and contending approaches to post-war reconstruction. Russia and Iran’s visions on the future of Syria include diverging views on military reform and economic investment. However, these disagreements are unlikely to lead to a breakdown of the relationship. Moscow and Tehran learned from their experience mitigating tactical disagreements in military campaigns and are more likely to delimit spheres of interests within Syria as both seek to reap the political and economic benefits of close linkages to Damascus. The experience of close cooperation and sustained contacts has simultaneously improved Moscow and Tehran’s ability to address the burgeoning challenges of a post-war settlement in Syria.

Background: Russian Hesitation, Then Commitment

In the months leading up to the Russian intervention in Syria, a series of high-level meetings between Russian and Iranian officials established the basis for a coordinated strategy to support Assad. In January 2015, Ali Akbar Velayati, foreign policy adviser to Iran’s supreme leader Ayatollah Khamenei, met with President Putin and Minister of Defense Sergei Shoigu in Moscow to deliver a letter from Khamenei. The visit itself was intended to spark a dialogue between Moscow and Tehran on the possibility of greater assistance to Syria, including the prospects of intervention. The meeting was preceded by a bilateral agreement on military-technical cooperation and high-level meetings in Tehran between Iranian military officials and Sergei Shoigu, the first time in 15 years that a Russian defense minister paid an official visit to Iran. Moscow initially rebuffed requests by Qassem Soleimani, the now-deceased Islamic Revolutionary Guard Corps (IRGC) Quds Force general, in January and February 2015 to travel to Moscow with the objective to convince Putin of the gravity of the situation in Syria; instead, Soleimani met with Lavrov during the Russian foreign minister’s visit to Tehran in March 2015.

The Russian receptiveness to Iran’s outreach occurred against the backdrop of a rebel resurgence in northwest and southern Syria combined with the Islamic State (IS) offensive in the northeast. These military campaigns led to the rapid reduction of the territory controlled by the Syrian government throughout the spring of 2015. With the IS advance into Palmyra in May 2015, the threat that the regime in Damascus might fall and the country might break up became increasingly plausible. The regime’s tenuous hold on power compelled Assad to publicly announce that the Syrian army lacked the necessary resources to contain the rebel advance and would thus focus on defending the most important areas. From July 24 to July 26, Soleimani covertly met with Putin and Shoigu in Moscow to coordinate the military operation in Syria. Shortly after Soleimani’s trip to Moscow, Russia and Syria signed a secret basing agreement for Khmeimim airfield in northern Syria. Around this time, a series of media reports indicated a growing presence of Russian military hardware and personnel on the ground in Syria, which the Russian Foreign Ministry described as “supplying military equipment to official Syrian authorities to fight terrorists.” By late September, Moscow announced the establishment of the Baghdad Information Center—a joint intelligence-sharing center in Baghdad between Russia, Iran, Iraq, and Syria with the primary function to coordinate intelligence against the IS and operations around the Syrian-Iraqi border.

Russia and Iran: Military Coordination with Different Goals

The Russian and Iranian campaign in support of the Syrian government developed an “integrated grouping” of irregular armed formations under the command of the Russian Armed Forces. Colonel-General of the Armed Forces of the Russian Federation Aleksandr Dvornikov, who commanded the Russian army group in the Syria from September 2015 to July 2016, noted that due to the low efficiency of the General Staff of the Syrian Armed Forces, all the work on preparing operations was carried out by officers from Russia’s Aerospace Forces (VKS), Navy, and Special Operations Forces. To facilitate Russian coordination with these groups, liaison elements from Syrian intelligence, IRGC combat detachments, Hezbollah, Al-Quds, and National Defense Forces were placed at the Russian command post in Khmeimim. To improve diplomatic and military communication, Iran appointed former defense minister and then-secretary of the Supreme National Security Council Ali Shamkhani to a newly created position specifically to coordinate policy with Russia on the military campaign in Syria. Soleimani served as Iran’s main point of contact with the Russians for military operations in Syria until his assassination in January 2020.

Even though Iranian forces were crucial to Russia’s military strategy, Moscow has remained wary about the excessive influence of Iranian-backed militias and non-state actors in a post-war Syria. From the onset of its military campaign, Moscow focused its efforts on the restoration of the combat capability of the Syrian Army. It sought to train a unified and professionalized force akin to Syria’s 25th Special Mission Division while providing the Syrian Army with weaponry—including T-90 tanks, modern armored personnel carriers, and unmanned aerial vehicles. Russia has relied on General Suheil al-Hassan’s 25th Special Mission Division (formerly known as the Tiger Forces) and Zayd Salih’s 5th Volunteer Assault Corps to reinforce its leverage in Syria.

Even though Iranian forces were crucial to Russia’s military strategy, Moscow has remained wary about the excessive influence of Iranian-backed militias and non-state actors in a post-war Syria.

By contrast, Iran’s ability to transfer weapons to the Syrian Army beyond armored vehicles and small arms has been restricted by IS control of northern Iraq and eastern Syria combined with the challenges of military transport aviation. Moreover, Tehran had a different set of goals altogether. With the Assad regime’s territorial gains, Tehran focused on entrenching its influence in the provinces of Aleppo, Homs, Deir ez-Zor, and the Lebanese borderland through pro-Iranian local groups and militias including Iraqi and Afghan militias, Hezbollah, and the Local Defense Forces.

Western Syria and Aleppo: Challenges of Coordination and Consolidation of Power

During the initial stages of the campaign, the lack of Russian air support for Iranian forces highlighted the challenges of integrating and coordinating IRGC and Iranian-backed ground forces with the Russian Armed Forces. The Jaysh al-Fatah siege of Khan Touman—a city southwest of Aleppo—caused Iran to suffer approximately 80 to 100 casualties of IRGC and proxy forces, one of its largest military losses in the Syrian Civil War. Several senior Iranian military officials drew attention to the lack of air support in Khan Touman as a veiled criticism of the Russian military’s public relations spectacle in Palmyra, which included a symphony by Russia’s Mariinsky Theatre. Tabnak, a paper owned by a senior IRGC officer, outwardly attacked Russia’s “indifference" toward Iranian losses in Khan Touman and argued that Russia “should play a greater role in sharing of military tasks with Syria and its allies” instead of holding a “leisurely” symphony in the ruins of Palmyra. Statements from Iranian officials have periodically surfaced ridiculing Russia’s widely publicized public relations campaign celebrating its military operations, reflecting a general sentiment in Tehran that Moscow’s interest in Syria has more to do with projecting its status as a great power.

In June 2016, the tripartite summit of the Iranian, Russian, and Syrian defense ministers in Tehran focused on the ongoing military campaign in Aleppo—the success of which would bolster Assad’s leverage over a future political settlement—and Deir ez-Zor. The ministers secretly discussed the deployment of Russian aircraft to Shahid Nojeh Air Base in western Iran, which would allow Russia to save fuel and significantly reduce flight time. The plan to use Iran’s airbase materialized in August 2016, and Russian aircraft flew from Shahid Nojeh to strike IS and Jabhat al-Nusra targets around Aleppo, Deir ez-Zor, and Idlib.

However, the widely publicized nature of these aviation operations provoked a backlash in Tehran and eventually led to the withdrawal of Russian forces within a week. Iran’s historical aversion to the presence of any kind of foreign military base on its territory, codified in Article 146 of the Constitution, was apparent as multiple parliamentarians challenged the legal basis of Russian military presence. Iranian defense minister Dehghan criticized Russia’s announcement of its use of Shahid Nojeh Air Base as an act of “grandstanding and incivility” intended “to prove that [Russia] is a superpower and can influence all regional and global affairs.”

Nevertheless, leaks began to surface about Russia’s continued use of the airbase following Alexander Lavrentiev’s secret meeting with Ali Shamkhani in which Iran apparently agreed to allow Russian long-range bombers overflight rights and permission to land at Shahid Nojeh Airbase for refueling. Though Russia’s continued use of the base is unconfirmed, Russia has used Iranian airspace for overflight throughout the campaign.

The tensions in the Russia-Iran relationship that emerged during the Khan Touman and Shahid Nojeh incidents are often overstated by analysts, yet both cases show the challenges posed by the expansion of cooperation in military campaigns. By mid-December, the Russia-Iran-Syria coalition recaptured eastern Aleppo from opposition forces, giving rise to a fragile nationwide ceasefire agreement brokered by Russia and Turkey. The siege of Aleppo illustrated Tehran and Moscow’s joint effort to further Assad’s consolidation of power in Syria, thereby enhancing the Syrian government’s status in a political settlement. Moreover, the success of the Russia-Iran-Syria entente in Aleppo served as a precursor to Moscow’s diplomatic aspirations to become “the indispensable power broker" in the Middle East.

Russia’s campaign in Syria has also reinforced its broader diplomatic aspirations to project its status as a great power in the Middle East. Whereas the General Staff of the Russian Armed Forces has led Moscow’s Syria policy, the Foreign Ministry has adeptly used diplomacy to capitalize on and, at times, facilitate military success on the battlefield. In particular, the inception of the Russian, Iranian, and Turkish-led Astana Process provided Russia, Iran, and Turkey with a parallel and more congenial track to the UN-led Geneva process to determine the political settlement of Syria. As the Syrian regime regained control over long stretches of the Syrian-Iraqi and Syrian-Jordanian borders, the Astana process facilitated the establishment and demarcation of four “de-escalation zones” across Syria.

Deir ez-Zor and Southern Syria: Regional Entanglements

After Aleppo, the Syrian government coalition concentrated on regaining territory from the IS in central Syria around Damascus and eastern Syria on the border with Iraq. Russian and Iranian coordination on the Deir ez-Zor campaign focused on a three-pronged assault on the strategically important territories in the east including the Baghdad-Damascus highway and oil fields located on the eastern bank of the Euphrates River. A campaign joint operating room, established by the General Soleimani and led by Iran, Hezbollah, and the Syrian military, ran part of the operation in Deir ez-Zor with the support of the Russian and Syrian Armed Forces. In early September 2017, Syrian troops broke through the blockade of Deir ez-Zor, which had been controlled by IS for more than three years. In November 2017, ground forces retook Abu Kamal on the Syrian-Iraqi border after the Popular Mobilization Forces (PMU) brought the Iraqi border town of al‑Qa’im under its control. The defeat of the IS in the eastern part of Deir ez-Zor, parts of the Badia, and territory around Homs allowed the IRGC to assert its presence within Syria while Iraqi groups on the border with Syria such as Kata’ib Hezbollah, the PMU’s Badr Brigades, and Harakat Hezbollah al-Nujaba contributed to the strengthening of Iranian influence along the Syrian-Iraqi border.

Beginning in 2018, Iran spearheaded the initiative to increase the Baghdad Information Center’s profile in the joint operations on the Syrian-Iraqi border. Iran’s minister of defense Amir Khatami’s visit to Baghdad in April 2018 coincided with the Iraqi airstrikes in Deir ez-Zor, announced during a meeting at the center with Iraqi, Syrian, Russian, and Iranian representatives. Despite the intensification of strikes on its militias by Israel and the United States, Iran has continued to operate near U.S. forces on the Syrian-Iraqi border. In October 2018, the military forces of Iran, Syria, and Russia held joint drills in the Deir ez-Zor province along the western bank of the Euphrates River. This occurred only one month after Russia blamed Israel for tampering with Syrian missile defense systems that resulted in the accidental downing of the Russian Il-20M plane by Syrian forces over Latakia. With the resurgence of IS attacks at the end of 2020, the border city of Abu Kamal in Deir ez-Zor witnessed a Russian military deployment ―the first of its kind since the city was seized from the IS at the end of 2017.

The increase of Russian presence in Deir ez-Zor prompted tactical disagreements between Russian and Iranian-backed ground forces. During the campaign against IS sleeper cells, Iran-backed militias provided direct military support to the Syrian 5th Corps. However, Iranian desires to assume the command of military operations were a source of tension until spring of 2021, when this appeared to be taken up at the ministerial level. At the same time, Iranian-backed militias controlling Abu Kamal provided auxiliary support to Russian military police in the establishment of several checkpoints in the city while the Russian-backed 5th Assault Corps, deployed near Abu Kamal, took over several posts previously held by Iran-backed al-Nujaba and Iraqi Hezbollah forces. By enmeshing its groups with pro-Russian ones, the IRGC sought to inhibit Israeli and American airstrikes on Iranian-backed militias operating in Syria and Iraq. Despite this, the Russian deployment in Deir ez-Zor failed to thwart U.S. airstrikes on Iranian forces in February 2021.

Like Deir ez-Zor, southern Syria became embroiled in the broader regional conflict between the United States, Russia, Israel, and Iran. In the spring and summer of 2018, the Syrian regime’s offensive in Daraa signaled a breakdown of the deescalation zone brokered by the United States, Russia, and Jordan in southern Syria. Russia launched its first airstrikes in the region in over a year as Syrian Army and Iranian ground forces such as the IRGC, the Afghan Fatemiyoun, Imam Hussein Brigade, and the Lebanese Hezbollah captured Busr al-Harir and Mlehat al-Atash, splitting the remaining rebel-held territory in Daraa Province. The regime’s success in Daraa occurred during a period of mounting regional tensions as Israeli airstrikes continued to target Iranian military facilities with IRGC and Hezbollah forces in southern Syria.

As part of its broader balancing act between Israel and Iran, Moscow engaged in diplomacy with Tel Aviv, which resulted in an agreement to limit Iranian proxy forces at least 83 kilometers from the Israeli border and to station Russian military police in the Golan Heights. But ​​Israeli pressure on Russia to restrain Iran’s deployments in the region has also demonstrated the limits of Moscow’s ability to exert influence over IRGC and Iranian-backed militias in the region. Russia has sought to limit the presence of pro-Iranian groups on the borders with Israel by integrating parts of the former opposition into the 5th Corps, yet competition between Hezbollah and Iranian backed groups continues in Daraa and Quneitra. Despite Israeli and U.S. pressure on Russia to manage Iran in Syria, it is unlikely Russia will be able to control Iran’s military posture in Syria or halt supplies to Hezbollah and other pro-Iranian groups in the region.

Beyond the Battlefield: The Future of Syria

The military campaign to preserve Assad’s regime in Syria has compelled Russia and Iran to adapt to the challenges of joint military cooperation on the battlefield through the establishment of bureaucratic channels and command structures. The experience of closer coordination in Syria and the overall improvement of Russia-Iran relations over the past decade suggests that Moscow and Tehran will be better equipped to manage the ascendant challenges facing the future of Syria. Therefore, disagreements about the transition from the military campaign to political and economic reconstruction in Syria does not foreshadow a breakdown in Russia’s relations with Iran.

However, Russia and Iran do compete for contracts in the energy, phosphate, agriculture, and real estate sectors in Syria, which has been compounded by the absence of an overarching framework or mechanism to coordinate investment between Moscow and Tehran. At times, Russia has secured contracts in the phosphate, oil, and gas sectors to the detriment of Iranian business interests.

Therefore, disagreements about the transition from the military campaign to political and economic reconstruction in Syria does not foreshadow a breakdown in Russia’s relations with Iran.

Notwithstanding the potential areas of friction over economic reconstruction, Russia and Iran have cooperated on sanctions evasion. For example, Russia and Iran have delivered oil to the Syrian government by using Promsyrioimport, a subsidiary of the Russian Ministry of Energy initially used to evade sanctions under Moscow’s “oil for goods” scheme with Iran prior to the Joint Comprehensive Plan of Action (JCPOA). Sanctions evasion may continue as an area of cooperation between Russia and Iran in Syria as sanctions on Moscow, Tehran, and Damascus persist, intensified by the Caesar Act.

Just as Russia and Iran have managed to resolve tactical disagreements between local proxy forces in the military campaign through bureaucratic and military channels, Moscow and Tehran will likely delimit spheres of interests within Syria as both seek to reap the political and economic benefits of close linkage to Damascus. Russia’s relationship with Iran demonstrates Moscow’s ability to compartmentalize its foreign policy by concentrating on areas of cooperation to mitigate tensions elsewhere in the relationship. Such logic has manifested in Syria. Therefore, it is misguided to overstate disagreements between Russia and Iran in Syria as indications of a deteriorating partnership. Despite long-standing mistrust and weak economic ties, Moscow and Tehran have strengthened and institutionalized their ties as a result of the experience of military cooperation in Syria.

Nicole Grajewski is an international security fellow at the Belfer Center for Science and International Affairs in the Harvard Kennedy School of Government and a doctoral candidate in the Department of Politics and International Relations at the University of Oxford.

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Nicole Grajewski

International Security Fellow, Belfer Center for Science and International Affairs, Harvard Kennedy School of Government