US House panels conducting impeachment inquiry into President Donald Trump release transcripts from closed-door depositions with former White House adviser Fiona Hill and current White House adviser Alexander Vindman.
House Democrats released new transcripts of the testimonies of President Trump's officials on Friday as they pushed their impeachment inquiry into the US president toward next week's public hearings.
The investigators released hundreds of pages of testimony from Fiona Hill, a former White House Russia adviser, and lieutenant colonel Alexander Vindman, an army officer assigned to the National Security Council.
Both testified about their concerns as Trump pressed Ukraine to investigate Democrats.
Vindman alerted superiors on two occasions, including after he listened to the July call in which Trump personally appealed to Ukrainian President Volodymyr Zelenskiy to investigate political rival Joe Biden and the outlier theory of a Ukrainian role in the 2016 US presidential election.
A whistleblower's complaint about that call triggered the impeachment probe.
US-Ukraine relationship 'is damaged'
Vindman told lawmakers there was "no ambiguity" that a US ambassador told Ukrainian officials to investigate Biden and his son, according to the testimony.
"There was no ambiguity, I guess, in my mind. He was calling for something, calling for an investigation that didn't exist into the Bidens," Vindman said, referring to Gordon Sondland, the US ambassador to the European Union.
Vindman said the US-Ukraine relationship "is damaged" and "will continue to be damaged and undercut."
Trump insisted earlier on Friday he has not been damaged by testimony detailing efforts by him and his administration to pressure Ukraine.
Speaking to reporters as he left on a campaign trip to Atlanta, Trump said he was "not concerned about anything" that has been disclosed so far.
Trump aide refuses to testify
Meanwhile, White House acting Chief of Staff Mick Mulvaney snubbed demands by House impeachment investigators to testify on Friday, claiming immunity as a top aide to President Trump.
As Trump again blasted the probe as "corrupt" and a "witch hunt," Mulvaney rejected a subpoena from the House Intelligence Committee to appear for a closed-door interview.
The brush-off came days ahead of Democrats taking their impeachment investigation public with what promises to be highly contentious open hearings in Congress starting next week on Wednesday.
The investigation has gathered evidence that Mulvaney was a key player in Trump's alleged extortion of Ukraine to further his personal political goals.