a whistleblower in the U.S. intelligence community filed a complaint in August regarding the leaders’ conversation. According to reports, the whistleblower was concerned that Trump pressured Ukrainian President Volodymyr Zelensky to investigate former Vice President and current Democratic presidential hopeful Joe Biden. Trump and others in his orbit have alleged without evidence that, while he was Vice President, Joe Biden blocked Ukrainian officials from investigating his son Hunter Biden’s business activities in the country. The Washington Post has reported that, ahead of the call, Trump told his Administration to withhold $400 million in military aid for Ukraine, which is fighting a separatist movement in the country’s east.
https://time.com/5685947/trump-ukraine-call/