TEHRAN, Young Journalists Club (YJC) - "I am calling on all my countrymen in Germany: the Christian Democrats, SDP [the Social Democrats], the Green Party are all enemies of Turkey. Support those political parties who are not enemies of Turkey," Erdogan told reporters after Friday prayers in Istanbul.
He accused those parties of being involved in "aggressive, disrespectful attitudes against Turkey."
The Turkish president said, "I invite them to teach a lesson to those political parties at the ballot box."
Germany is set to hold parliamentary elections on September 24, with Chancellor Merkel running for a fourth term, Presstv reported.
Berlin has slammed Erdogan for "interference" in Germany's elections, condemning his statements as an attempt to incite Germans against each other.
"That is an unprecedented act of interference in the sovereignty of our country," German Foreign Minister Sigmar Gabriel told the RedaktionsNetzwerk media group on Friday.
"Erdogan's interference in Germany's electoral campaign shows that he wants to incite people in Germany against each other," he added.
Merkel has said there would be no expansion of the European Union's customs union with Turkey or a deepening in the EU-Turkish relations, remarks which have angered Ankara.
Erdogan said on Friday that Merkel's comments showed Germany had become a country that violates the European Union's body of law.
Relations between Turkey and Germany began to deteriorate after a failed coup in Turkey in 2016. Germany has repeatedly criticized Ankara's crackdown on the suspects of involvement in the coup, saying the Turkish government has acted beyond the rule of law.
Turkey defends the crackdown and insists that the government in Berlin has failed to properly condemn the coup.
Ankara also accuses Berlin of giving sanctuary to outlawed Kurdish militants and allowing their sympathizers to stage anti-Turkey rallies across Germany.