US says IS damaged by coalition air strikes in Syria
The US armed forces chief says Islamic State (IS) militants are being damaged by air strikes in Syria but air power alone is not enough to defeat them, the BBC reported.
Gen Martin Dempsey said a political solution and a ground campaign would both be needed in Iraq and Syria.
Gen Dempsey said that up to 15,000 fighters - to be drawn from Syria's moderate opposition - would be needed for a ground force in Syria.
On Friday, the UK agreed to join US-led air strikes on IS in Iraq.
French fighter jets are already taking part in strikes in Iraq and Belgium and Denmark are also sending planes.
Speaking at the Pentagon, Gen Dempsey said this week's strikes in Syria had disrupted IS's command, control and logistics capabilities.
He said it would take more than air power to recapture lost territory in Syria and neighbouring Iraq but a ground force did not need to involve US troops.
"In fact, ideally for the kind of issues we are confronting there, the only truly effective force that will actually be able to reject Isil (IS) from within its own population is a force comprised of Iraqis and Kurds and moderate Syrian opposition," he said.