Turkish Prime Minister Ahmet Davutoglu on Sunday called for military backing for Syria's "moderate opposition" to create a "third force" in the war-torn country to take on the Damascus regime as well as Islamic State militants.

The call comes as Turkey faces international pressure to step in to defend the mainly Kurdish Syrian border town of Kobane from IS jihadists.

"We need a security force to protect the Syrian people both from IS and the regime," the premier said in an interview with the pro-government Sabah daily.

"The solution is a third force....which represents the Syrian people and is made up of Syrians, not foreign fighters," he was quoted as saying, adding that such a force should represent all Syrian factions, including the main exiled opposition group, the Syrian National Coalition.

The Turkish parliament this month gave the government the green light to take military action against IS in Iraq and Syria but Turkey's military has yet to make a move.

Following growing criticism over Ankara's perceived failure to intervene in Kobane, the United States on Friday reported "progress" in pressing Turkey to participate in the fight against IS.

"Turkey has agreed to support, train and equip efforts for the moderate Syrian opposition," State Department deputy spokeswoman Marie Harf said.

Turkey has repeatedly said that Syria will only know peace once Bashar al-Assad's regime has been defeated, and that US-led air strikes alone won't be enough to halt the IS advance in Kobane.

Turkey has called for a buffer zone to protect its border and provide some protection for fleeing Kurds, but the idea has been coolly received by allies.