Turkish government representatives have addressed their supporters in Germany in person several times in recent years.
Appearances by former prime minister and current President Recep Tayyip Erdogan have come in for particular criticism.
February 10, 2008: Erdogan warns Turks in Germany against too much assimilation. "Assimilation is a crime against humanity," he said, addressing around 16,000 supporters in the western city of Cologne.
February 27, 2011: Speaking in front of around 10,000 people in Dusseldorf, Erdogan calls on his compatriots to integrate, but once again rejects complete assimilation: "Our children must learn German, but they must learn Turkish first."