Gordon Sondland

Updated at 4:40 p.m. ET

Fiona Hill, who served as the top Russia expert on the National Security Council before resigning last summer, criticized Republicans on the House Intelligence Committee for advancing theories that Ukraine, and not Russia, interfered with the 2016 presidential election.

Testifying on the third and final day of impeachment hearings before the panel this week, Hill said, "I would ask that you please not promote politically driven falsehoods that so clearly advance Russian interests."

A career diplomat who overheard a U.S. ambassador's phone chat with President Trump this summer in which Trump allegedly referred to "investigations" to be carried out by Ukrainian officials is set to testify in the Democratic-led impeachment inquiry Thursday.

David Holmes, a senior staffer at the U.S. Embassy in Ukraine, is expected to expound on testimony he gave to lawmakers last week behind closed doors.

President Trump, Vice President Pence, Secretary of State Mike Pompeo and much of officialdom was "in the loop" throughout the Ukraine affair, a key witness told Congress on Wednesday in watershed testimony.

Gordon Sondland, the U.S. ambassador to the European Union, rejected the idea that he was part of any back channel or shadow effort.

He said he conferred with the State Department and the National Security Council all this year as he and other envoys worked to try to get concessions for Trump from Ukrainian President Volodymyr Zelenskiy.

Updated at 7:08 p.m. ET

Gordon Sondland, the U.S. ambassador to the European Union, tied President Trump directly to conditioning a meeting with the Ukrainian president with "a public statement from President Zelenskiy committing to investigations of Burisma and the 2016 election."

When Gordon Sondland arrived at the Capitol last month to provide what would be pivotal testimony in the Trump impeachment inquiry, a reporter asked the U.S. ambassador to the European Union, "Are you here to salvage your reputation?"

"I don't have a reputation to salvage," Sondland shot back.

Until recently, Sondland, 62, had a pretty low profile outside his hometown of Portland, Ore., where he and his wife, Katy Durant, are big Republican donors and contributors to numerous arts and civic organizations.

Editor's note: This is a developing story and will update with more details of the testimony.

Updated 6 p.m. ET

Updated on Jan. 20 at 11:15 p.m. ET

President Trump deputized lawyer Rudy Giuliani to run a shadow foreign policy for Ukraine outside the State Department, witnesses told Congress this past week — and the White House said people should "get over it."

It has been a busy week. Here's what you need to know about the latest in the Ukraine affair and the impeachment investigation.

Mister mayor

Giuliani has been an important figure in Trump world for years, but what investigators heard was how central he was in the plan to get Ukraine's government to launch investigations that Trump wanted.

Updated at 7:35 p.m. ET

White House chief of staff Mick Mulvaney acknowledged several substantial facts about the Ukraine affair on Thursday — but disputed that it was inappropriate or that the administration even was trying to hide what it had done.

Mulvaney acknowledged that President Trump expected concessions from his Ukrainian counterpart in exchange for engagement and also that Trump had empowered his personal lawyer, Rudy Giuliani, to run what has been called a parallel foreign policy for Ukraine on his own.

As the U.S. ambassador to the European Union, Gordon Sondland has an important job, though it's not a position that makes someone a household name.

So how has he become a crucial player in the controversy that could jeopardize the Trump presidency?