The commander of foreign operations for Iran's elite Revolutionary Guards visited Russia last week and met President Vladimir Putin, Fars news agency reported on Wednesday, a sign of closer ties as their regional alliance gains momentum.
General Qassem Soleimani, head of the Quds Force, last visited in July to aid in planning the Russian military intervention in Syria. Russia and Iran support Syrian President Bashar Assad against rebels in that country's civil war.
Backed by Russian air strikes, hundreds of Iranian troops have arrived in Syria since late September to take part in a pro-government ground offensive, their biggest deployment in the country to date.
Soleimani has been subject to an international travel ban and asset freeze by the UN Security Council since 2007 for his alleged role in illicit arms trafficking and smuggling nuclear materials.
"General Soleimani held a meeting with President Putin and high-ranking Russian military and security officials during a three-day visit last week... They discussed the latest developments in Syria, Iraq, Yemen and Lebanon," Fars said, quoting unnamed sources.
Soleimani has helped lead Iran's efforts to fight armed insurgents in Syria and neighboring Iraq and reports directly to the Islamic Republic's Supreme Leader Ayatollah Ali Khamenei.