The third day of House public impeachment hearings begins Tuesday morning with testimony from two White House officials who listened in on President Trump's July 25 phone call with Ukrainian President Volodymyr Zelensky. Both witnesses — the top Ukraine expert on the National Security Council, Lt. Col. Alexander Vindman, and his counterpart at Vice President Mike Pence's office, Jennifer Williams — both told House investigators in close-door depositions that they were discomfited by Trump's request to Zelensky for a favor involving investigations of Joe and Hunter Biden and the Democratic National Committee. Trump has slammed both on Twitter.

On Tuesday afternoon, Trump's former Ukraine special envoy Kurt Volker and former NSC official Tim Morrison will testify. Morrison also has first-hand knowledge of the July 25 call, which he described to House investigators as concerning but not, in his opinion, violating any laws. Republicans had requested to hear from Volker and Morrison.

The public impeachment hearings will pick up again on Wednesday with testimony from U.S. Ambassador to the European Union Gordon Sondland, who is emerging as a linchpin of Trump's pressure campaign in Ukraine, plus Pentagon official Laura Cooper and State Department official David Hale. Thursday will see testimony from David Holmes, a U.S. Embassy official in Kyiv who testified that he overheard a phone call Sondland made to Trump on July 26 from a cafe in Ukraine's capital, and former NSC official Fiona Hill will testify on Friday. Peter Weber