Former New York City Mayor Rudolph Giuliani has canceled a scheduled appearance as a paid speaker at the high-profile Russian-sponsored Eurasian Economic Union (EEU) event in Armenia. The Russian and Iranian presidents are also slated to address the gathering. Giuliani is facing questions about his own involvement in the Ukraine scandal after the formal launch of an impeachment investigation by Congress following a whistleblower complaint and the release of a readout of a telephone call that President Donald Trump had with the Ukrainian President Volodymyr Zelensky. Giuliani has for months been promoting a story that former Vice President Joe Biden had pressured Ukraine to fire its top prosecutor in order to purportedly protect his son Hunter Biden.

Giuliani was the only American invited to speak at the EEU event. In the past, Giuliani has avoided scrutiny despite attending and speaking at several such conferences.

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But, now, with evidence mounting that he has been running a shadow foreign policy in Ukraine, allegedly even marginalizing senior officials like former National Security Advisor John Bolton, his role is coming increasingly under attention. This week, Giuliani was served with a subpoena to hand over documents to Congress about his role in the Ukraine affair.