Vladimir Putin has discussed working with international "partners" to take on Islamic State militants, according to Russian media.
The Russian president was reported to have talked about the issue with his Security Council today.
Kremlin spokesman Dmitry Peskov would not say which countries Russia may be willing to work with.
Iranian president Hassan Rouhani has issued a strongly-worded condemnation of Islamic State terrorists he says are trying to "kill humanity".
In an interview with NBC News, Mr Rouhani said IS murders of civilians were contrary to Islamic teachings.
"From the viewpoint of the Islamic tenets and culture, killing an innocent people equals the killing of the whole humanity," Mr Rouhani said.
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President Obama - a leader who thought his legacy would be ending two conflicts - has plunged the US into the maelstrom of two civil wars.
A social media campaign imitating the popular Ice Bucket Challenge has gone viral. Its target is Islamic State.