Russia is already arming and training former Syrian President Bashar al-Assad's troops and rumors of more active involvement have been growing, with reports that Russia is establishing a base close to Assad-held territory.
On Wednesday, Reuters reported that Russian forces had started participating in small numbers in military operations in Syria, citing three unnamed Lebanese sources familiar with political and military developments in Syria.
According to Russian state news agency RIA Novosti, this week Russian President Vladimir Putin himself said: "To say we're ready to do this today – so far it's premature to talk about this. But we are already giving Syria quite serious help with equipment and training soldiers, with our weapons."
Syria is mired in civil war, following a series of nationwide protests that begun in 2011 and met with violence from Assad's government. Since then, the proliferation of insurgent groups, including IS, has led Assad to lose control of large swathes of Syria.
With the world's focus on the millions of refugees from the conflict, particularly those trying to enter Europe, the West is under more pressure to do something, or at least seem to be doing something, to solve the crisis. Hundreds of thousands of Syrians have been killed in the fighting and around 9 million displaced, with more than 4 million Syrians now refugees in neighboring countries, according to the United Nations Refugee Agency.