In a tweet, he called for press freedom, democracy and the rule of law to be reinstated in Turkey before relations could be normalized.
In an interview with German public radio ahead of Turkish Prime Minister's Binali Yildirim's visit to Berlin on Thursday, he urged Merkel to stop "cuddling" with Turkey, given Ankara's crackdown on dissenters, journalists and activists.
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Özdemir, who has Turkish roots and has been a staunch critic of President Recep Tayyip Erdogan for years, claimed that Berlin had "no clear Turkey policy" and that the latest coalition agreement made barely any mention of human rights violations and how to deal with them.
He said Ankara should not receive any "economic assistance" until German journalist Deniz Yücel, who has been in a Turkish jail for a year now without charge, was freed. And even then, he stressed, "all would not be well in Turkey."
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He also urged Merkel to talk to Yildirim about the controversial offensive against the Kurdish YPG in Syria's Afrin .
Left party chimes inLeft party parliamentary group leader Sahra Wagenknecht also tweeted that Merkel should not "cozy up" to Erdogan and his government given the "catastrophic human rights situation" and the "war in Syria against the Kurds." She also called for EU accession talks and weapons exports to Turkey to be stopped.
Özdemir and Wagenknecht called for Yücel to be freed without concessions. "Everything else would be a slap in the face of Deniz Yücel, who explicitly said he wouldn't want to be part of any dubious exchange deals," Özdemir told German news agency dpa.
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Wagenknecht told dpa that it was "unbearable that Yücel has been detained for a year now and still Turkey continues to receive millions of euros worth of loans from Europe."
Ahead of his visit to Germany, Yildirim said he was hopeful that Yücel could be released soon. German Foreign Minister Sigmar Gabriel recently said that he thinks there may be some "movement" in the case.
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The recent release of fellow journalist Mesale Tolu and activist Peter Steudtner had eased tensions with Ankara, but according to Reporters without Borders, there are more journalists are in jail in Turkey than in any other country.
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