One of the chiefs of the outlawed Kurdistan Workers Party (PKK) said on Saturday it had called all its fighters back to Turkey, after violent protests over the government's policy on Syria left dozens dead.

Cemil Bayik, one of the founders of the PKK which has waged a bloody 30-year insurgency for Kurdish self-rule in Turkey, warned that the peace process was in danger of collapse and attacks could resume after the deadly unrest.

The United States reported "progress" Friday in pressing Turkey to participate in the fight against the Islamic State group, noting a pledge from Ankara to train and equip moderate Syrian rebels.

The head of the U.S.-led coalition, retired general John Allen, and U.S. pointman on Iraq, Brett McGurk, completed a two-day visit in Turkey to press the NATO ally to engage militarily against the jihadist group that has taken over a wide swath of Syria and Iraq.

Kurdish fighters halted a thrust by Islamic State group jihadists towards the heart of the battleground Syrian town of Kobane Saturday, after the U.N. warned thousands of civilians risked massacre.

The pre-dawn attack came after the IS militants overran the Kurdish headquarters in the border town on Friday, sparking fears they would cut off the last escape route to neighboring Turkey.

Gulf monarchies taking part in U.S.-led air strikes against the Islamic State jihadist group in Syria could deploy special forces on the ground but only if certain conditions are met, analysts say.

Sunni-ruled Saudi Arabia, Bahrain, Qatar and the United Arab Emirates have joined air strikes on the IS, which has seized swathes of Syria and neighbouring Iraq.

France said Friday it was willing to unblock two key chapters of negotiation for Turkey's bid to become a member of the European Union.

Foreign Minister Laurent Fabius told reporters: "Today, I am announcing that France is ready to open new chapters for negotiations, notably chapters 23 and 24", which refer to fundamental rights and justice.

The head of the main Kurdish political party in Syria on Friday called on Turkey to allow its territory to be used for passing weapons to Kurdish fighters defending the key Syrian town of Kobane.

Salih Muslim, the leader of the Democratic Union Party (PYD), told Agence France-Presse that Turkey should understand that the Kurds are not a "threat" for Ankara.

Clutching a bloodstained napkin used by her brother just before his death, a young Syrian Kurdish woman mourned for the 23-year-old killed while defending the key town of Kobane from Islamic State insurgents.

The young man was killed fighting alongside People's Protection Units (YPG) against Islamic State (IS) jihadists for control of the mainly-Kurdish Syrian town, just over the Turkish border.

Thousands of Syrian Kurds who fled the Islamic State jihadists' assault on the town of Kobane have moved from Turkey to Iraq or back to safer parts of their homeland, the U.N. said Friday.

"We are seeing growing numbers choosing to continue their journey, either by heading to the Kurdistan region of Iraq or else crossing back into Syria several hundred kilometers to the east," said Adrian Edwards, spokesman for the U.N. high commissioner for refugees.

President Recep Tayyip Erdogan on Friday vowed to press on with efforts to make peace with Turkey's Kurds despite deadly pro-Kurdish protests, saying he would work for an agreement until "my last breath".

Protests by pro-Kurdish demonstrators angry at the government's policy on Syria have left 31 dead in Turkey and raised fears that the fragile peace process with Kurdish rebels could be derailed.

Turkish President Recep Tayyip Erdogan on Friday accused Syrian President Bashar Assad of waging "state terror", equating the crimes of the Damascus regime with those of Islamic State (IS) jihadists.

Ankara is concerned that the focus of the U.S.-led coalition on fighting IS extremists will take attention away from Turkey's long-standing aim of toppling the Syrian leader.