Russian defense officials confirmed on Tuesday that its warplanes are staging from an air base in Iran’s western province of Hamedan to launch sorties against jihadist and rebel groups in Syria. The confirmation follows yesterday’s report by the Arab outlet Al Masdar.

The Russian defense ministry reported that Tupolev-22M3 bombers and Sukhoi-34 strike fighters took off from Hamedan and hit targets in the provinces of Aleppo, Idlib, and Deir al Zour today. The Russian defense ministry has also reportedly requested permission from the Iraqi and Iranian governments to use their airspace for launching cruise missiles. These developments facilitate Russian operations in Syria in support of Bashar Assad, an ally of both Moscow and Tehran.

Contrary to extant Western reporting, however, this would not be the first time that Russian bombers have used the base in Hamedan to launch operations in Syria since the Kremlin’s military intervention began in October 2015.

AllSource satellite imagery in December 2015 identified Russian planes at the same military base in the western Iranian province of Hamedan, also known as Shahid Nozheh Air Base (as analyzed here by the American Enterprise Institute). The Russian Air Force, however, has primarily flown its jets from Mozdok military base in southern Russia along a corridor through the Caspian Sea, Iran, and Iraq to strike targets in Syria, as noted by The Aviationist.

There has been an uptick in high-level meetings between Iranian and Russian officials over the past two months, where the two sides have discussed Syria and increasing bilateral cooperation. Ali Shamkhani, the secretary of Iran’s Supreme National Security Council, attended a meeting between the Iranian and Russian defense ministers in Tehran in early June. Shamkhani followed up with a trip to Moscow later that month, where he met with senior Russian defense officials.

It was Shamkhani who confirmed to Iranian media the report of Russian jets using Iran’s airbase. The senior Iranian official hailed Russo-Iranian cooperation against “terrorism” as “strategic,” and noted that Iran would put its “facilities at Russia’s disposal in its war against terrorism.”

As noted by the Associated Press, American officials are said to have been cognizant of such an eventuality, but surprised at Moscow’s recent decision to deploy aircraft in Hamedan. That same report cited a senior Russian lawmaker who framed the move as largely financial. State Department Spokesman Mark Toner, however, said in a press conference that the move would “not necessarily” shut the door for prospective US-Russia military collaboration in Syria. Toner also announced that the deployment of Russian bombers to Iran may violate United Nations Security Council 2231, which endorses the Iran nuclear deal also known as the Joint Comprehensive Plan of Action (JCPOA) and prohibits arms transfers to Iran for five years (Russia has a permanent seat at the Security Council).

The use of the Hamedan air base is a logical step for both Iran and Russia. The Russian air base in Hmeimim, Syria cannot house large Russian bombers. Hamedan has an extensive military complex capable of hosting large bombers safe from immediate military threats. This substantially trims the flying time of Russian missions by a reported 60 percent, and allows bombers to carry at least double in payloads, thus increasing the tempo and firepower of Russian aerial operations in Syria. Russia may also use Hamedan air base as a transit point for refueling and transferring munitions for bombing raids, while restocking supplies in Russian bases. For its part, Tehran may have sought weapons deals in exchange for Russian access to Hamedan base, according to a senior Moscow-based analyst cited by The Wall Street Journal. Iranian media outlets close to the IRGC reported that the Iranian armed forces had purchased AK-103 assault rifles from Russia. The sale of small arms are not covered under resolution 2231.

The latest developments indicate that Russia will rely more on Iran’s military air base to conduct sorties. It also suggests that Russia and Iran do not plan to draw down their support for the Assad regime in Syria any time soon, and that they are ready to boost bilateral military cooperation in new ways if need be. The war in Syria is at a critical moment now, as pro-regime and opposition forces fight for the control of Aleppo.

Behnam Ben Taleblu is a Senior Iran Analyst at Foundation for Defense of Democracies. Amir Toumaj is a Research Analyst at Foundation for Defense of Democracies.

Are you a dedicated reader of FDD's Long War Journal? Has our research benefitted you or your team over the years? Support our independent reporting and analysis today by considering a one-time or monthly donation. Thanks for reading! You can make a tax-deductible donation here.