Istanbul, Turkey (CNN) -- Turkey's main opposition leader resigned as head of his party Monday after the circulation of a videotape allegedly showing him having an affair with a female party deputy who had once been his secretary. Deniz Baykal declared that "there is a conspiracy against me" and blamed the government for the video. The 71-year-old chairman of the Republican People's Party said the secretly shot tape could not have been made without the approval of the ruling party. "It is impossible to organize such a plot within such a short period of time without the knowledge of the ruling party," he said in a televised address. "One who gives credit to unlawful and unethical plots cannot defend law and ethics."
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Deniz Baykal blames government for allowing secret video recording
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"There is a conspiracy against me," Baykal says
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Resignation comes ahead of referendum on constitutional changes opposed by Baykal
Deniz Baykal
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He added that he found Baykal's statements "just as ugly and worthless as the tape" and noted that @placeholder had not denied its authenticity.