According to the sources who spoke on condition of anonymity due to restrictions on talking to the media, Erdogan gave information to Merkel on Turkey’s Operation Euphrates Shield in northern Syria.

Erdogan and Merkel also discussed recent developments in Aleppo, the wider Syrian issue and the fight against terrorism, the sources added.

Since Sept. 19, when the Syrian regime ended a week-long cease-fire brokered by the U.S. and Russia, almost 500 civilians have been killed and hundreds injured in attacks on Aleppo.

Syria has been locked in a vicious civil war since 2011, when the Bashar al-Assad regime cracked down on pro-democracy protests – which had erupted as part of the Arab Spring uprisings – with unexpected ferocity. 

The Syrian Center for Policy Research, a Beirut-based NGO, has put the death toll from the six-year-old conflict at more than 470,000.