Syrian rebels and their allies the jihadist Al-Nusra Front on Saturday withdrew from Kasab, a strategic village on the border with Turkey they seized in March, a monitoring group said.

Most fighters from Al-Nusra and the other rebel groups pulled out, "leaving behind only a small number" of men, said the Syrian Observatory for Human Rights.

Turkey received prior warning of the attack on its consulate in the northern Iraqi city of Mosul, Deputy Prime Minister Bulent Arinc said Friday, defending Ankara's decision not to evacuate.

Arinc told reporters that the Turkish government had made contact by telephone with the hostages and they had "not been exposed to any bad treatment."

Austria warned Turkish Prime Minister Recep Tayyip Erdogan on Thursday not to say anything that may "split" Austrian society when he visits next week following a contentious visit to Germany.

The strongman leader ruffled feathers last month when he made disparaging remarks about a German opposition leader of Turkish origin and spoke out against "assimilation" in a speech in Cologne.

Turkey said Thursday it is holding talks to secure the release of dozens of its citizens kidnapped by Islamist militants in northern Iraq amid international calls for their release.

"We are in touch with all the groups in Iraq including Kurds and Turkmens," a government official told Agence France Presse, without giving further details.

The United States on Thursday condemned the kidnappings of Turkish citizens in an attack by Islamist militants who have seized swathes of  northern Iraq, and called for their immediate release. 

Samantha Power, the U.S. permanent representative to the United Nations, said the actions of the jihadist group the Islamic State of Iraq and the Levant (ISIL) were a threat to the region.

The trial of more than two dozen anti-government protesters began in Turkey on Thursday with one defendant blasting the charges against them as "ridiculous" and Amnesty International denouncing the process as a "show trial".

Twenty-six members of the Taksim Solidarity umbrella group, including doctors, architects and engineers, face lengthy prison terms for their part in leading the protests a year ago, with the prosecutor calling for 13-year jail terms for the five main suspects.

Turkish activists who helped launch mass anti-government protests last year will go on trial on Thursday in what critics have said is a further attempt to crush dissenting voices.

Twenty-six alleged leaders of Taksim Solidarity, an umbrella group of civil society, union and political groups, face up to 29 years in prison for their part in the demonstrations that marked the biggest challenge yet to the 11-year rule of Prime Minister Recep Tayyip Erdogan.

Militants stormed the Turkish consulate in the northern Iraqi city of Mosul on Wednesday and kidnapped 48 people including the head of the mission, a Turkish government official said.

"Forty-eight Turks including the consul, staff members, guards and three children were abducted," the official told Agence France Presse, speaking on condition of anonymity.

Turkish dissident sociologist Pinar Selek vowed to fight on after Turkey's highest appeals court on Wednesday overturned a life sentence for her alleged involvement in a 1998 explosion that killed seven people.

"The fight continues because they have only canceled the sentence," she told Agence France Presse by telephone from Strasbourg in France, where she has political asylum.

A Turkish imam has been allowed to rock on after the country's powerful religious authorities gave him the green light to continue playing in his band after a nine-month investigation.

Ahmet Muhsin Tuzer, a Muslim religious leader from a tiny hamlet on Turkey's Mediterranean coast was investigated by the Diyanet, the state body in charge of the country's mosques.