Ukraine call pressures Zelensky to investigate Biden

In a phone call with Ukrainian President Volodymyr Zelensky, Trump repeatedly pushed for Ukraine to investigate political rival Joe Biden and his son Hunter. After discussing U.S. support for Ukraine, Trump said "I would like you to do us a favor though because our country has been through a lot and Ukraine knows a lot about it." Trump asked Zelensky to work with his personal lawyer Rudy Giuliani and Attorney General William Barr on the investigation. At the time, Trump had frozen $400 million in congressionally-mandated military aid to Ukraine. Multiple officials later testified that Trump wanted political favors in exchange for the aid (quid pro quo). The call became the centerpiece of Trump's first impeachment.

"I would like you to do us a favor though" — Phone call with Ukrainian President Zelensky