US vows 'lasting defeat' against IS, says killed 8,500 militants

New Pentagon chief Ashton Carter on Monday vowed "lasting defeat" against the Islamic State group as he summoned top generals and diplomats to Kuwait to review the war effort against the militants. 

Speaking to American troops at the US Army base of Camp Arifjan before the talks, Carter said the US-led coalition was "pressing" the IS group "very ably from Kuwait and elsewhere".

"And we will deliver lasting defeat, make no doubt," he said.

The discussion would look not just at the fight in Iraq and Syria, where US and coalition aircraft have carried out daily bombing raids, but the wider regional struggle against IS, he said.

"ISIL is not just a threat to Iraq and Syria. It's a larger threat to the region," said Carter, using an alternative acronym for the militant group.

Asked by one soldier if Washington would consider sending ground troops to take on the militants, Carter said any additional military action would have to be weighed carefully. 

But he added "we'll do what it takes" to prevail. 

Recruiting Sunnis to fight IS

Carter would be looking for an update on the Iraqi government's efforts to recruit other Sunnis into the fight against IS, a senior US defence official told reporters.

Commanders believe the air war against IS and the training of Iraqi soldiers is mostly on course, but Baghdad's Shiite-led government has more work to do to persuade Sunnis to take up arms.

"On the military side, things are going well," the official said, adding however that "it's still yet to be seen how the Iraqis are really going to lead this thing."

"Thousands" of Sunni tribesmen have signed up to fight but a proposed Sunni national guard was still a long way off, the official said.

"Are Sunnis in the fight? Yes. Are they in the numbers we want? No."

Iraqis fighting to recapture western town from IS

About 800 Iraqi forces backed by US warplanes are waging a battle to retake the western town of Al-Baghdadi from IS, Lieutenant General James Terry, who oversees the US-led war effort against IS, said on Monday.

Kurdish militia, meanwhile, rebuffed an attempt by the IS group on Sunday night to recapture an Iraqi town standing on a crucial supply route to the northern city of Mosul, the commander said.

Terry told reporters the militants had been "halted" across Iraq and that it was now only able to launch smaller-scale attacks.

Terry, who is headquartered in Kuwait, said that while the IS militants are under mounting pressure, the Iraqi army was improving.

"The capabilities that we're seeing in the Iraqi security forces are growing," the general said.

"At the same time, what we're not seeing on the part of Daesh (IS) is as important also. We're not seeing those broad counter-offensives" that they staged previously, he said.

Airstrikes 'kill 8,500' IS fighters

Meanwhile, a senior US military figure has claimed that airstrikes against IS in Iraq and Syria have killed 8,500 fighters.

US Central Command chief, General Lloyd Austin, was speaking while meeting Iraqi Defence Minister Khaled al-Obeidi on Monday.

The comments reported by the Iraqi defence ministry. Austin claimed that the situation in the country better than before.

The US and partner nations have carried out more than 1,300 air strikes against IS in Iraq and Syria since operations began in August, according to the force.

Meanwhile, the Syrian Observatory for Human Rights said on Monday that US-led air strikes against IS in Syria have killed more than 1,600 people, mainly militants, since they began five months ago.

The Observatory said almost all of those killed were fighters from IS and Al-Qaeda's Syrian affiliate Al-Nusra Front, though it also documented the deaths of 62 civilians.

The Britain-based monitor said the strikes that began on September 23 had killed 1,465 members of the Islamic State group, most of them non-Syrians.

Another 73 fighters from Al-Nusra Front were killed, along with a man from a rebel group being held prisoner by IS in the group's de facto capital Raqa.