Turkish President Recep Tayyip Erdogan on Wednesday vowed to fight on against Kurdistan Workers' Party (PKK) militants, in the face of mounting attacks on security forces blamed on the Kurdish rebels.

"Let me put it clearly, the operations will continue," he said in a televised speech in Ankara, as Turkey presses on with air strikes on PKK targets in the country's southeast and in northern Iraq.

"We will never stop in the face of all these attacks. We will continue to fight with determination," he added.

Erdogan vowed "no concessions" in the fight against "terror", saying: "A state subjected to an armed attack has the right to defend yourselves with arms."

Turkey is currently pressing a two-pronged "anti-terror" offensive against Islamic State (IS) jihadists in Syria and PKK militants following a wave of attacks.

But, so far, the air strikes have overwhelmingly concentrated on the separatist Kurdish rebels, to the frustration of Western commentators who want to see Turkey ramp up its involvement in the fight against IS.

The state-run Anatolia news agency reported over the weekend that so far 390 "terrorists" had been killed in the campaign against the PKK.

But the Kurdish rebels have hit back, leaving a 2013 truce declared by the PKK in tatters.

According to an AFP toll, 29 members of the security forces have been killed in violence linked to the PKK since the current crisis began.

Erdogan called on the PKK, which is blacklisted as a terrorist organisation by Ankara and much of the international community, to law down arms and bury them "under concrete".

Until it did so, the Turkish state would continue its offensive, he said.

"The most important task of a state is to protect lives."

"We extended our hand but they responded with arms," Erdogan said, referring to the Kurdish militants, reaffirming his verdict that the peace process was now "on ice".

Erdogan launched a new bitter attack on the leader of the pro-Kurdish People's Democratic Party (HDP), Selahattin Demirtas, who Erdogan accuses of being a front for the PKK.

Picking up on a recent visit to Brussels by Demirtas, Erdogan said: "The party that is controlled by a terrorist organisation is looking for a solution in Brussels."

"It has become so alienated from an understanding of its own country and nation that it must look for a solution elsewhere."

In a sometimes bombastic speech, Erdogan also claimed that US President Barack Obama had pleaded with him for Turkey to help prevent the fall of the mainly Kurdish Syrian town of Kobane to IS jihadists in 2014.

"Mr Obama reached me and said 'there are two days left before Kobane falls'. And he said 'here we want to have your help'."