An impeachment inquiry against Donald Trump was initiated by House Speaker Nancy Pelosi on September 24, 2019, after a whistleblower alleged that President Donald Trump had abused the power of the presidency by withholding both military aid and a White House meeting as a means of pressuring newly-elected President of Ukraine Volodymyr Zelensky to publicly announce investigations which would be damaging to Trump's political rival Joe Biden in the 2020 election.