Oct. 21 (UPI) -- Acting U.S. Ambassador to Ukraine William Taylor is among the Trump administration officials scheduled to testify in the House this week as part of Democrats' impeachment investigation.
Taylor was involved in exchanges of text messages among administration officials this summer following President Donald Trump's phone call with Ukrainian leader Volodymyr Zelensky, which led to a whistle-blower report and the House inquiry.
At least one witness is scheduled to testify each day between Tuesday and Friday.
Taylor is scheduled to appear Tuesday to detail his stated concerns that Trump had withheld military aid to Ukraine to pressure Kiev to investigate political rival Joe Biden and his son, a former executive for a Ukrainian gas company.
In text messages with U.S. Ambassador to the European Union Gordon Sondland and former Special Envoy to Ukraine Kurt Volker, Taylor said withholding aid for a political favor would be wrong. Sondland testified last week, and also said leveraging military aid would be wrong.
Several other witnesses have already testified in the investigation, which is trying to determine if Trump withheld the aid to pressure Ukraine to investigate the Bidens. Joe Biden is a Democratic candidate for president next year. Trump has acknowledged withholding the aid, temporarily, and pressing Zelensky for a Biden investigation, but has maintained the two were never connected. Sondland also made that clear in his text messages to Taylor.
White House chief of staff Mick Mulvaney said last week Trump withheld the aid because of concerns about corruption in the Ukrainian government, not to pressure for an investigation of the Bidens.
House Democrats will look to Taylor to corroborate the claims.
Phil Reeker, the acting official at the State Department for European and Eurasian affairs, and Michael Duffey, associate director for national security programs at the Office of Management and Budget, will testify on Wednesday. Thursday, two Pentagon officials will appear to discuss military aid to Ukraine.
The White House has said it will not cooperate with the impeachment inquiry until the full House votes to approve the investigation.