Russia used Iran as a base to launch air strikes against Syrian militants for the first time on Tuesday, causing analysts to speculate that the Kremlin's ties with Tehran were getting closer. Long-range Russian Tupolev-22M3 bombers and Sukhoi-34 fighter bombers were launched from the Hamadan air base in Iran, aimed at targets in the civil war-torne Syria.

According to Reuters, this is the first time Russia has used a different nation's territory to launch its attacks in Syria. The Kremlin began its bombing campaign in support of Syrian President Bashar al-Assad in September last year. Moreover, the last time Iran allowed another nation to use its territory for military operations was during the Islamic revolution in 1979. Moving through Iran will allow the Russian air force to shorten the length of its flights and use its bombs more efficiently.

The head of Iran's National Security Council was quoted by state-run Islamic Republic News Agency as saying Tehran and Moscow were now sharing facilities to fight against terrorism, calling their cooperation strategic. Iran and Russia have boosted their bilateral ties since international sanctions against the West Asian nation were lifted after it agreed to curb its nuclear programme.

Pavel Felgenhauer, a Russian military analyst told Al Jazeera, "It’s not just Russian planes touching down in Iran. To establish an operational base, they’d have to move hundreds of servicemen as well as thousands of tonnes of munitions, fuel, [and] other equipment to operate heavy bombers from an Iranian base. So this is actually Russia establishing a rather sizable military presence inside Iran."