Activists of the "Attac" network wear masks of (L-R) French President Emmanuel Macron, Turkish President Recep Tayyip Erdogan, US President Donald Trump, German Chancellor Angela Merkel, Britain's Prime Minister Theresa May, and Russian President Vladimir Putin as they demonstrate in Hamburg, northern Germany, on July 4, 2017.
On Tuesday, Turkey protested officially to Germany after an artist was allowed to set up an installation in central Berlin offering a auto as a prize in exchange for killing world leaders including Erdogan.
"Do you want this vehicle?" Then kill the dictator. Is a direct incitement to violence, "the Turkish Foreign Ministry underlined".
The ministry added that Ankara expects Berlin to take measures to prevent such provocative actions.
Turkey's embassy to Berlin said it was "incomprehensible and unacceptable" that Ruch had been allowed to set up such an installation with no intervention from the local security forces.
Erdogan's latest outburst came after Germany refused to allow him to address members of the large ethnic Turkish community in a rally in Germany ahead of the G20 summit.
Turkey's worsening relations with its old allies including Germany, the European Union and the United States will have an impact on the Balkan region, too, experts say. German politicians have restricted Erdoğan's speaking to people of Turkish origin living in Germany.
The group has almost 14,000 followers in the country, from whom it annually collects more than €13 million (over $14 million), according to the reports of German domestic intelligence agency, BfV.