Obama Gives Putin His Best Death Stare At The G20 Summit In China (Photos)

Barack Obama and Vladimir Putin have met for 'pull-aside' meetings at the G20 summit in China but failed to agree on a solution to the Syrian civil war.

Washington and Moscow support opposing sides in the bloody five-year conflict, which has left 300,000 people dead and forced millions to flee. 

The two leaders discussed Syria at closed multilateral meetings but could not reach a deal to ease fighting in the war-torn region.

But in their final face-to-face meeting before Obama leaves office in January next year, they agreed to keep up negotiations over a cease-fire agreement.

A senior US administration official said they had a longer-than-expected discussion during a 'constructive' meeting.

It comes as Syrian government troops - backed by Russia - resumed their siege of the city of Aleppo.