Bolstering allegations that the White House engaged in a cover-up to suppress evidence of wrongdoing by President Donald Trump, a National Security Council official who listened to Trump's July conversation with Ukraine's leader reportedly told House impeachment investigators Tuesday that the administration intentionally omitted key details from the rough transcript of the call it released last month.

The New York Times reported that Lt. Col. Alexander Vindman, the NSC's top Ukraine expert, told House committees during his sworn deposition that the transcript left out "crucial words and phrases" that he unsuccessfully attempted to reinsert.

"Thanks to today's impeachment testimony, we now know White House officials deleted key details out of the record of Trump's Ukraine call before they released it. It was never a transcript. It was a cover-up."

—Swing Left

"The omissions, Colonel Vindman said, included Mr. Trump's assertion that there were recordings of former Vice President Joseph R. Biden Jr. discussing Ukraine corruption, and an explicit mention by Ukraine's president, Volodymyr Zelensky, of Burisma Holdings, the energy company whose board employed Mr. Biden's son Hunter," according to the Times.

"Colonel Vindman did not testify to a motive behind the White House editing process," the Times added. "But his testimony is likely to drive investigators to ask further questions about how officials handled the call, including changes to the transcript and the decision to put it into the White House's most classified computer system."

The details emerging from Vindman's testimony, which lasted more than 10 hours, were viewed by lawmakers and legal experts as more damning evidence of Trump's misconduct and of his administration's deliberate efforts to hide the wrongdoing from the public.

"Wow. This is just stunningly bad for the White House. A full on cover-up," tweeted CNN legal analyst Susan Hennessey. "How much longer are congressional Republicans going to continue to go along with this?"

As Common Dreams reported, the White House decided to release the rough transcript of Trump's call with Zelensky last month in an attempt to dampen outrage over a whistleblower complaint about the conversation, during which the U.S. president pressed Zelensky to investigate Biden.

Speaking to reporters outside the White House earlier this month, Trump said he "had an absolutely perfect conversation" with Zelensky and "on top of that, and maybe less importantly, frankly, but on top of that, we have a transcript of the conversation, fortunately, that's perfect."

"The transcript is a perfect transcript," Trump added. "There shouldn't be any further questions."

Rep. Don Beyer (D-Va.) pointed to the president's characterization of the transcript in a tweet responding to the Times report.

"This is damning: for weeks Trump called the call record which showed he sought foreign influence in our elections a 'perfect transcript,'" said Beyer. "It was a doctored transcript. The White House cut out some of his words, refused to restore them, and hid the transcript in a secure server."

Breaking: Thanks to today’s impeachment testimony, we now know White House officials deleted key details out of the record of Trump’s Ukraine call before they released it. It was never a transcript. It was a cover-up. https://t.co/Eh12VW6rVi — Swing Left (@swingleft) October 30, 2019

Following Vindman's deposition Tuesday, House Democrats unveiled a resolution detailing the next steps in their impeachment inquiry into Trump. The House is scheduled to vote on the resolution Thursday.

As NBC News reported, "the eight-page resolution calls for public hearings and lays out their general format, and specifically permits staff counsels to question witnesses for periods of up to 45 minutes per side, Democrats and Republicans."

Rep. Pramila Jayapal (D-Wash.), a member of the House Judiciary Committee, said the resolution "will ensure a fair and public process for the American people to see the damning and full picture of the president's betrayal."