(CNN) Germany should "formally suspend" talks on EU membership with Turkey, the chair of the German Parliament's foreign affairs committee said Monday, warning of a slide towards authoritarianism.

"My view is that we should formally suspend negotiation talks with Turkey as long as Erdogan is establishing and conducting authoritarian power," German Member of Parliament Norbert Röttgen, a close ally of Chancellor Angela Merkel, told CNN's Christiane Amanpour.

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"We must not give up on Turkey. Erdogan is not Turkey. But we have to make clear that now it is Erdogan's rule which is being established more and more in Turkey."

President Erdogan on Monday evening told a rally in Ankara that some in Europe were "threatening" to freeze talks -- "but," he told the crowd, "let me tell you that this is not that important for us anyway."

He clashed with European leaders during the campaign over cancelled rallies planned in Europe, accusing German and Dutch leaders of "Nazi practices."

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