Iran and Russia have finalized an agreement to trade in their local currencies instead of the US dollar, Iran's state media reported on Wednesday.
The agreement was finalized during a meeting between the governors of the two countries central banks in Russia, it said.
Both Iran and Russia are subject to US sanctions.
"Banks and economic actors can now use infrastructures including non-SWIFT interbank systems to deal in local currencies," state media said.
Members of the Russian-led Eurasian Economic Union (EEU) signed a fully-fledged free trade agreement with Iran on December 25.
Iran has become increasingly important for the Kremlin after Western sanctions over Moscow's conflict in Ukraine limited Russia's foreign trade routes and forced it to look for markets outside Europe.
Iranian authorities have said military cooperation with Russia is expanding. Iran said in November it had finalized arrangements for Russia to provide it with Su-35 fighter jets, Mi-28 attack helicopters, and Yak-130 pilot training aircraft.