Munter argued that, in Syria, Russia was trying to be taken seriously as a global power.

"I think it's an overarching goal of the Russians to make sure that they're seen as taken seriously throughout the region, that they're present throughout the region, and they're recognized as being there throughout the region. So they're going to, I think, make it clear to the public even at the risk of maybe ticking off the Iranians that they have influence throughout the region, "said Munter in an interview with VOA's International Edition on August 23. 

"Whether or not that has a strategic goal—that is whether they're better at fighting the rebels, whether that makes more of a difference—seems to me to be less important than the message that Russia's there, Russia's there to stay and Russia has a wide reach."

Russia last week revealed that a number of their fighter bombers had taken off from Hamadan, south-west of Tehran, to carry out strikes in Syria. It was the first time a foreign state had used Iranian territory to attack a third country since at least the second world war.

Munter also believed the armed conflict, which is in its fifth year and has killed hundreds of thousands, could be resolved.

"Any situation like this can be resolved but it's a question of people making choices or being compelled to make choices. It's a question of with whom do people ally themselves ... People make choices because they see things change or they feel their own ability to affect things changes. And when the right constellation of change takes place, this war can be solved," said Munter.

To listen to the full interview, click here. Munter's segment starts at the 11:45 mark.