German Chancellor Angela Merkel is in Ankara to discuss efforts to manage the migration crisis as some 35,000 Syrians fleeing fresh attacks by regime forces are stranded at the Turkish border.
Merkel is scheduled to meet Turkish Prime Minister Ahmet Davutoglu on Monday, followed by talks with President Recep Tayyip Erdogan.
Turkey's cooperation is crucial in Merkel's efforts to reduce the influx of migrants and refugees into the European Union through stronger policing of the bloc's external borders.
In exchange, the bloc has given the go-ahead for a 3-billion-euro (3.3-billion-dollar) aid package for Turkey aimed at improving the lives of the more than 2.5 million Syrian refugees living there.
At home, Merkel is resisting unilateral measures demanded by members of her government including stricter German border controls and an upper limit on the number of new arrivals.
Merkel last visited Turkey in October and the two countries held bilateral consultations less than four weeks ago.
Groups including the Turkish community in Germany have called on the chancellor to raise Ankara's human rights record during her visit, especially the government offensive against Kurdish rebels in the country's south-east.