Turkey summoned Germany's ambassador to express its fury over a Frankfurt rally where protesters brandished insignia of outlawed Kurdish militants, the presidential spokesman said on Sunday, denouncing it as a "scandal".
In his Sunday speech, Erdogan accused Merkel personally of using Nazi methods against his "Turkish brother citizens in Germany and brother ministers".
(Vatican Radio) Germany's government has cast doubt on Turkey's chances of joining the European Union, amid growing tensions with Ankara over human rights and Turkey's claim that it's being treated unfairly by countries in western Europe.
Chancellor Angela Merkel today warned that Germany could ban future campaign events by Turkish politicians on its soil unless Ankara stopped "Nazi" jibes aimed at Berlin.
Erdogan had previously accused the German and Dutch governments of engaging in "Nazi practices" after both countries prevented Turkish ministers from campaigning at events for expatriate voters ahead of an upcoming referendum.
It appears that Turkey is not attempting to fix its relations with Europe ahead of the country's constitutional referendum, which will take place on April 16. The refusal drew a strong rebuke from the Turkish president who said that the spirit of Nazi Germany was still rampant in Europe.
"Who would really benefit from it if we paid back in kind, if we answered using the same language as the Turkish president", said the ministry spokesman, Martin Schaefer. "Because these are useful instruments for Germany to use against Turkey".
The Turkish government also bristled at comments by the head of Germany's BND foreign intelligence agency questioning Ankara's accusation that a failed coup attempt last July was masterminded by the influential US -based Turkish cleric Fethullah Gulen.
The vote is created to change the Turkish constitution to give Erdogan sweeping powers.
In an interview published by German weekly Der Spiegel, Germany's foreign minister suggested that for now the most that Turkey can hope for is to one day achieve a "privileged partnership" with the 28-nation bloc.
Erdogan also accused the detained journalist, Yücel, of being a "terrorist spy" and vowed he would not be released but charged.
"They gave it to the ones who would be hosting it for the second time, not who would host it for the first time", said Erdogan, referring to the fact that Tokyo hosted the Games in 1964.