He says if House investigators want to see a summary of the April 21 call, he's "happy to give it to them".
Democrats want to build a strong public case that Trump abused his presidential powers by pressuring Ukraine to launch corruption investigations involving the son of Joe Biden, the former vice president who is vying to be the Democratic nominee to run against Trump in the 2020 presidential elections.
Republicans have also accused Democratic House leaders of holding the inquiry in secret because they are closed-door, although Republican committee members have been present throughout. Democrats initially said they wanted the whistleblower to testify in a closed-door hearing but reversed themselves after it was revealed that at least one staff member of House Intelligence Chairman Adam Schiff (D-Calif.) met with the person before the complaint was filed.
William Taylor, the top U.S. diplomat in Ukraine, and George Kent, another career diplomat with experience in the country, will testify on Nov 13.
Lieutenant Colonel Alexander Vindman, an NSC official who testified before the committees later in October, said in his testimony that Hill, his supervisor, raised concerns to Sondland after Sondland raised the prospect of Ukraine opening investigations in exchange for a White House visit.
While the appearance drew praise from Trump, it also raised alarms from critics already wary of his independence after Barr released a letter summarizing the reports' conclusions, which Mueller later complained "did not fully capture the context, nature and substance" of the full report and led to "public confusion about critical aspects of the results of" the investigation.More news: New wave of European Disney+ launches on March 31
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Bolton, who was sacked by Trump in September, was also called to appear on Thursday but did not show, and his attorney said he would not testify voluntarily. CNN has reached out to the White House for comment.
Former U.S. ambassador to Ukraine Marie Yovanovitch will testify on Friday.
Bolton, who was sacked by Trump in September, was called to appear on Thursday, but Bolton's attorney said he would not testify voluntarily, and he has not yet been subpoenaed.
They are trying to determine whether Trump froze $391 million United States in security assistance for Ukraine to put pressure on Zelensky to conduct the investigation, misusing USA foreign policy for his personal gain. Pence has said he and the Ukrainian president did not discuss Biden during their closed-door meeting, but they did discuss the White House's decision to halt security aid meant to counter Russian aggression.
If the Democratic-controlled House votes to impeach Trump, the Republican-controlled Senate would then hold a trial on whether to remove him from office.
Republican leadership have assigned Rep. Jim Jordan to serve on the House Intelligence Committee during the open impeachment hearings against President Trump next week.