WASHINGTON – A new revelation in public testimony from Ambassador Bill Taylor, the top U.S. diplomat in Ukraine, was that one of his aides overheard a phone call July 26 between President Donald Trump and Gordon Sondland, the U.S. ambassador to the European Union, in which the president inquired about "the investigations."

Trump had requested that Ukrainian President Volodymyr Zelensky  investigate former Vice President Joe Biden's son Hunter, who sat on the board of a Ukrainian gas company that had been under investigation, as well as alleged Ukrainian interference in the 2016 presidential election. U.S. intelligence has found no evidence of Ukrainian meddling in 2016. 

Taylor testified before the House Intelligence Committee on Wednesday that his staffer asked Sondland what the president thought about Ukraine after the phone call, which came a day after Trump's conversation with Zelensky, which is the focus of the impeachment inquiry. Sondland said, "President Trump cares more about the investigations of Biden," than U.S. policies on Ukraine, according to Taylor.

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Taylor delivered an opening statement that largely echoed his closed-door testimony at hearings Oct. 22. He said he arrived in Kyiv on July 17 and discovered two diplomatic tracks that provided “a weird combination of encouraging, confusing and ultimately alarming circumstances.” The channels of the official State Department and a back channel guided by Trump lawyer Rudy Giuliani quickly began diverging, he said.

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The ambassador shed more light on the Trump administration's decision to freeze $400 million in security aid for Ukraine over the summer, including attempts by senior administration officials to convince Trump to release the military assistance. Taylor said CIA Director Gina Haspel was among senior administration officials who tried to persuade Trump to lift the hold on Ukraine's military aid.

"My understanding was that the secretaries of defense and state, the CIA director, and the national security adviser sought a joint meeting with the president to convince him to release the hold, but such a meeting was hard to schedule, and the hold lasted well into September," Taylor said.

Also Wednesday, House Democrats scheduled two more interviews in the impeachment inquiry for Nov. 15 and 16, indicating that impeachment investigators have not concluded closed-door interviews with witnesses.

David Holmes, counselor for political affairs at the U.S. Embassy in Ukraine, is scheduled for Nov. 15.  Mark Sandy, an official in the Office of Management and Budget who failed to show up for a closed-door deposition last week, is scheduled for Nov. 16.

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Contributing: Nicholas Wu