READ: Impeachment Hearings Opening Statements for Wednesday Congress will hear from three witnesses on Wednesday, most notably U.S. Ambassador to the European Union Gordon Sondland.

READ: Gordon Sondland and Laura Cooper's Opening Statements

House committees are hearing from three witnesses Wednesday — following a busy Tuesday when four officials provided public testimony to impeachment investigators.

Gordon Sondland, the U.S. ambassador to the European Union, will testify solo in the morning starting at 9 ET. Laura Cooper, the deputy assistant secretary of defense for Russian, Ukrainian, and Eurasian Affairs, as well as David Hale, the undersecretary of state for political affairs, will testify in the afternoon.

Watch the hearing here.

NPR will post the witnesses' opening statements below as they are released.

Gordon Sondland

Ambassador Sondland's testimony comes after additional witnesses have told lawmakers that the ambassador played a significant role in pushing for Ukraine to investigate Burisma Holdings — the Ukrainian energy company for which Hunter Biden previously served as a board member.

On Nov. 4, Sondland said that he had known and informed Ukraine that U.S. military aid was being withheld until Ukraine made a statement announcing investigations into corruption — a disclosure that reversed testimony from his Oct. 17 closed-door deposition.

Read his opening statement here:

Laura Cooper

Cooper first testified behind closed doors on Oct. 23 that she was made aware in August by former U.S. envoy to Ukraine Kurt Volker that military aid was being withheld from Ukraine in hopes of a prepared announcement by Ukraine about election interference.

Read her opening statement here:

David Hale

Hale first testified in front of impeachment investigators on Nov. 6, when he told lawmakers that leading officials decided not to release a statement of support for ousted U.S. Ambassador to Ukraine, Marie Yovanovitch because of worries it would "make matters worse."

The State Department official holds the third-highest position in the department and told investigators that the decision to not publicly support Yovanovitch came from an official higher up than himself. "The secretary most likely would have been the person," Hale said in his testimony.

Hale did not deliver an opening statement Tuesday.