Turkey shells Kurdish positions in Syria for second day

Turkey shelled Kurdish-held positions on northern Syria for a second day on Sunday, complicating the region's multi-sided conflict and raising international concerns that the country's five-year war could be spiralling further out of control.

Turkish state media said that dozens of Kurdish fighters had been killed in the renewed shelling which came after Turkey told the Syrian Kurdish Democratic Union Party (PYD) to withdraw its fighters from territory it had taken in the past week from other opposition groups, including the Menagh air base.

Syrian opposition factions, including the al-Qaeda-affiliated Nusra Front, had retreated from the base and other areas in the face of Russian air strikes and a Syrian government advance around the northern city of Aleppo.

The US, which has provided support for Kurdish opposition forces in Syria, said it was working with both sides to de-escalate the situation.

State Department spokesperson James Kirby said the US had urged Turkey to stop its bombardment and urged the PYD not to take advantage of the changing situation on the ground in Syria to seize more territory.

“We are concerned about the situation north of Aleppo and are working to de-escalate tensions on all sides,” Kirby said in a statement.

Turkey will continue to strike back at Kurdish fighters of the Democratic Union Party (PYD) in Syria, Prime Minister Ahmet Davutoglu told German Chancellor Angela Merkel on Sunday, despite growing pressure on Ankara to stop the shelling.

In telephone talks, Davutoglu told Merkel that Turkey "will not permit the PYD to carry out aggressive acts. Our security forces gave the necessary response and will continue to do so," his office said in a statement.

France said that Turkey was worsening the situation in northern Syria, where a government advance around the city of Aleppo and hundreds of Russian air strikes has seen tens of thousands of people flee towards the Turkish border.

The French foreign ministry called on Sunday for "an immediate halt to the bombing, both that of the regime and its allies throughout the country and that of Turkey in the Kurdish zones".

Syria's government also condemned Turkey and called on the United Nations Security Council to take action.

"The foreign ministry strongly condemns the repeated Turkish crimes and attacks against the Syrian people and Syria's territorial integrity," state news agency SANA reported.

The ministry called on the UN Security Council to "put an end to the crimes of the Turkish regime".

Turkish police on Sunday clashed with pro-Kurdish protestors in a flashpoint district of Istanbul, leaving at least two wounded, an AFP photographer and reports said.

Police arrived in armoured vehicles and fired tear gas canisters, while wounded protesters were taken away on stretchers, the photographer said.

Zakariyya Karsli, a Turkmen rebel commander in northern Syria told Turkey's state-run Anadolu news agency that at least 29 PYD fighters had been killed as a consequence of artillery fire targeting the towns of Minnig, Maranas and Maryamin.

The UK-based Syrian Observatory for Human Rights also reported smaller numbers of Kurdish casualties.

Ankara considers the PYD and its YPG militia to be branches of the Kurdistan Workers Party (PKK), which has waged a decades-long separatist insurgency against the Turkish state.

Turkish Prime Minister Ahmet Davutoglu said on Saturday that he had spoken to US Vice President Joe Biden and told him that the PYD posed a direct threat to Turkey.

Saudi warplanes arrive in Turkey

The US and Turkey are NATO allies and partners in the international coalition fighting the Islamic State (IS) group in Syria and Iraq, with Turkey's Incirlik air base a major hub that is being used by the US and other nations for operations against IS in Syria.

A Saudi millitary spokesperson, Brigadier General Ahmad al-Assiri, confirmed late on Saturday that a number of Saudi war planes had arrived at the base to join the coalition effort, following earlier reports that Turkey and Saudi Arabia were ready to commit ground troops to the fight against IS if required.

But Assiri told Al Arabiya television network on Saturday that no Saudi ground forces had been sent to Turkey yet.

Turkey's Foreign Minister Mevlut Cavusoglu also said that no decision about a possible Turkish ground operation in Syria had been made, although he added that Turkey had long advocated that option.

Russian President Vladimir Putin and US counterpart Barack Obama on Sunday held telephone talks in which they had agreed to intensify diplomatic efforts to enforce a proposed agreement announced on Friday for the fighting in Syria to stop within a week, according to the Kremlin.

“The two presidents agreed to step up cooperation through diplomatic channels and other agencies in order to carry out the declaration the International Syria Support Group approved in Munich,” the Kremlin said, referring to the international security conference in the German city where the deal was struck.

The White House said that Obama had told Putin to halt air strikes against Syrian opposition forces.

Syria's foreign ministry on Sunday also accused Turkey of allowing a convoy of 100 Islamic militant fighters including "Turkish forces and Turkish mercenaries" to enter Turkish territory from rebel-held Idlib province and then cross back into Syria's Aleppo province at the Bab al-Salam border crossing.

The Syrian Observatory for Human Rights also reported the arrival of a convoy of fighters from Turkey at Bab al-Salam.

The complexity and shifting alliances of the battle in northern Syria was highlighted again on Saturday when US-backed Syrian Democratic Forces, an alliance of Kurdish and Arab fighters, launched an attack on Tal Rifaat, one of the few remaining rebel bastions north of Aleppo city, after the town had earlier endured at least 20 Russian air strikes.