Turkey will declare the German and nine other ambassadors undesirables in the dispute over imprisoned Turkish human rights activist Osman Kavala. He had instructed the Foreign Ministry to declare the diplomats "persona non grata" "as soon as possible," Erdogan said Saturday. In international diplomacy, classification as "persona non grata" is usually followed by expulsion.

The Turkish leader did not give a deadline. "They must get to know Turkey and learn to understand it," Erdogan said of the ten ambassadors, accusing them of "indecency." "They must leave here if they don't understand Turkey."

The ambassadors from Germany, France, the U.S. and seven other countries had issued a joint appeal earlier this week calling for the release of Kavala, a culture promoter who has been in prison without conviction for four years. Ankara called the appeal, which was unusual for diplomatic customs, "unacceptable."