Let them do it. "Germany, you don't have anything to do with democracy. Why are you disturbed?" he was quoted by Reuters as saying at a rally in Istanbul on Sunday.
"We can't continue negotiating about membership with a country that has been distancing itself from democratic norms and rule-of-law principles for years", Kern said. "We thought that era was in the past, but apparently it isn't", he continued.
German authorities withdrew permission for two meetings in German cities last week that were part of a government campaign to win the Turkish community's support for the next month's Turkish referendum on the constitution.
Gaggenau authorities said there was insufficient space for the rally.
Among Germany's 3 million Turkish community, almost 1.5 million of them are eligible to vote. Germany accounts for about 11 percent of Turkish imports.
He has been sharply criticized in western Europe for mass dismissals and arrests of suspected conspirators, from judges to journalists.
Andreas Scheuer, general secretary of the Bavarian CSU party, said that Erdogan's remarks marked a new low point in ties between the two allies and demanded an apology.
At the same time, public outrage is mounting in Germany over Ankara's arrest of a Turkish-German journalist.
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The Hammers beat Chelsea in the EFL Cup in October at the London Stadium in a match marred by crowd violence. Premier League football consistently shows that all managers are only a few bad games away from being fired.
Meanwhile, Turkish Prime Mnister Binali Yildirim said he had had a long phone call with German Chancellor Angela Merkel.
Another Bundestag member Julia Kloeckner told the local newspaper Bild that Erdogan's Nazi comparison is a "new peak of excess".
After Erdogan's outburst, Turkish Foreign Minister Mevlut Cavusoglu spoke by phone with German counterpart Sigmar Gabriel late Sunday, a call that came at the request of the German side, a Turkish official said on condition of anonymity.
"A common European Union effort to end this kind of campaigning would be a sensible thing to do".
"We don't want to see their fascist actions".
Just like in the U.S., it now appears that in Europe too when one needs to make a really "bold" political statement, the logical recourse is to just call one's adversary fascist, or simply "Nazi".
Dutch nationalist Geert Wilders, expected to make huge gains in a March 15 election, said on Sunday he would declare "the whole cabinet of Turkey persona non grata". However, Berlin questioned the Ankara's hunt-down and purge overseas, seeing it as violations of human rights. An EU migrant deal with Turkey, which also is a North Atlantic Treaty Organisation member, has significantly cut down the number of migrants crossing into Europe.