Turkey has demanded that 20 captured German members of "Islamic State" (IS) be repatriated, according to media reports.
"We need the full cooperation and active partnership of our allies in the fight against terrorism," Turkish President Recep Tayyip Erdogan's communications director, Fahrettin Altun, told Germany's Stuttgarter Nachrichten newspaper in an interview published Monday.
Read more: Turkey vows to return IS suspects to Europe
According to Altun, four German IS fighters have been captured since the Turkish military and allied militia began a cross-border military operation in northeast Syria against Syrian Kurdish-led forces on October 9. Another 16 German nationals who had joined the jihadi terrorist group were already in Turkish custody.
On Saturday, Turkish Interior Minister Suleyman Soylu criticized European states for not repatriating imprisoned IS members in Turkey.
"We are not a hotel for IS members from any country," he said.
Nearly 100 German IS members imprisoned: Interior Ministry
European states have been wary of repatriating their citizens who went to fight for an IS "caliphate" in Syria and Iraq, fearing a political backlash, complications with gathering evidence to convict them and the risk of extremist attacks at home.
Soylu's remarks were directed at several countries — including the Netherlands, Denmark and the United Kingdom — which have moved to strip dual national IS members of their citizenship or refused to repatriate them.
In June, the German parliament approved a change in the law to allow dual nationals to lose their citizenship if they fight for a foreign terrorist militia. The new law would not apply retroactively, meaning those who already joined IS or have been captured won't lose their citizenship.
In all, Turkey wants to send up to 1,300 foreign jihadis to their home countries — many of them to Europe.
In addition to those imprisoned in Turkey, Syrian Kurdish forces are holding around 11,000 IS fighters in prisons in northeast Syria, along with tens of thousands of women and children family members. Around one-fifth of the IS fighters imprisoned by Syrian Kurdish forces in northeast Syria are believed to be European.
According to the German Interior Ministry, more than 80 German IS members are imprisoned in Syria and Iraq. Syrian Kurdish forces and the United States have also demanded European states take back nationals who joined IS.