'This is all going to blow up': Highlights from Day 5 of impeachment hearings

“This is a fictional narrative that has been perpetrated and propagated by the Russian security services themselves,” said Hill, who until July served as the director for European and Russian affairs at the White House National Security Council.

Hill spoke on the final day of scheduled public testimony before the House Intelligence Committee probing whether Trump asked Ukraine to investigate a political rival in return for a White House meeting or the release of U.S. security aid.

If the committee calls no further witnesses, Hill’s request may set the stage for the Democratic-led House’s wider consideration of whether to draft formal charges known as articles of impeachment against the Republican president.

In her testimony, Hill also said Gordon Sondland, U.S. ambassador to the European Union, was engaged in a "domestic political errand," and warned him that not coordinating with her or following the proper interagency process would end badly.

"I did say to him, Ambassador Sondland, Gordon, 'I think this is all going to blow up,' and here we are," she told impeachment investigators.

David Holmes, a staffer from the U.S. Embassy in Ukraine, testified on Thursday about a July 26 phone call in which he said he overheard Trump ask Sondland about the status of the investigations into former Vice President Joe Biden.

“So, he’s gonna do the investigation?” Trump asked Sondland, referring to Zelenskiy, Holmes said.

“He’s gonna do it,” replied Sondland, he said.