Turkey summoned a senior German diplomat on Monday, a day after a rally in Cologne in support of the Turkish president who was not permitted to address the crowd by video link, reports AFP.
Turkish officials were also to meet with the top US military commander in the first direct talks since a failed coup on July 15, with Washington under pressure from Ankara to extradite the alleged mastermind, Islamic preacher Fethullah Gulen.
The coup aimed to unseat President Recep Tayyip Erdogan who has since launched a sweeping nationwide purge of suspected Gulen supporters, dismissing tens of thousands from their jobs and detaining almost 19,000 people. The crackdown has sparked international alarm, with Prime Minister Binali Yildirim admitting there may have been some unfair treatment in the dismissals.
"There must definitely be some among them who were subjected to unfair procedures," he said in comments published by state-run Anadolu news agency on Monday.
"We will make a distinction between those who are guilty and those who are not." In Germany, home to Turkey's largest diaspora, tens of thousands of Erdogan supporters rallied in Cologne on Sunday to demonstrate their opposition to the coup in an event held under tight security.
Hours before the demonstration, Germany's constitutional court rejected an application to show via video link live speeches from Turkey by politicians including Erdogan, over fears they could work up the crowd.
The decision sparked anger in Turkey, with presidential spokesman Ibrahim Kalin calling the move unacceptable and a "violation of the freedom of expression and the right to free assembly". A spokeswoman for the German embassy told AFP that the charge d'affaires had "been summoned to the Turkish foreign ministry at 1:00 pm (1000 GMT)" on Monday over the rally.
But Berlin played down the incident, saying such "invitations" were nothing out of the ordinary. "In the day-to-day dealings between countries, it is a daily event -- normal for a representative of a country to be called in to the foreign ministry of his host country," German foreign ministry spokesman Martin Schaefer told journalists.