Putin: Russia could join air strikes against Islamic State
Barack Obama and Vladimir Putin discussed the possibility of Russian involvement in the military campaign against the so-called Islamic State (IS) during their meeting on Monday.
In a meeting on the sidelines of the event, Barack Obama and Vladimir Putin agreed a political solution to the crisis was necessary, but continue to disagree on the fate of Syria's president Bashar al-Assad.
Obama labeled Assad a "tyrant", but Putin said it would be an "enormous mistake" to refuse to work with the Syrian government.
Secretary-general Ban Ki-moon has called for the situation in Syria to be referred to the International Criminal Court.
