Trump dismisses Mike Pence aide Jennifer Williams, who overheard Zelensky call, as 'Never Trumper'

William Cummings | USA TODAY

Show Caption Hide Caption Pence aide on Capitol Hill for impeachment probe Jennifer Williams, an aide to Vice President Mike Pence, is on Capitol Hill to testify behind closed doors in the impeachment investigation. Her appearance comes as former national security adviser John Bolton has so far failed to show up. (Nov. 7)

President Donald Trump fired off a tweet Sunday attacking another witness in the impeachment inquiry being conducted against him, dismissing an aide to Vice President Mike Pence as a "Never Trumper."

On Saturday, congressional investigators released the transcript from the closed-door deposition of Jennifer Williams, a foreign policy adviser to Pence who took notes during a July 25 phone call between Trump and Ukrainian President Volodymyr Zelensky. The call is a key aspect in the whistleblower complaint that alleged Trump was withholding military aid to Ukraine for political benefit.

In her testimony, Williams said the call "struck me as unusual and inappropriate."

"Tell Jennifer Williams, whoever that is, to read BOTH transcripts of the presidential calls, & see the just released ststement from Ukraine," Trump tweeted on Sunday. "Then she should meet with the other Never Trumpers, who I don’t know & mostly never even heard of, & work out a better presidential attack!"

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Tell Jennifer Williams, whoever that is, to read BOTH transcripts of the presidential calls, & see the just released ststement from Ukraine. Then she should meet with the other Never Trumpers, who I don’t know & mostly never even heard of, & work out a better presidential attack! — Donald J. Trump (@realDonaldTrump) November 17, 2019

When asked for comment on Trump's tweet, Pence press secretary Katie Waldman told CNN, "Jennifer is a State Department employee."

Trump has insisted that a rough transcript of the call shows he did nothing wrong. But Democrats say it demonstrates that Trump wanted a "favor" in the form of investigations in exchange for military assistance.

The president and his supporters have dismissed the impeachment inquiry as a politically motivated "hoax." And they have implied political bias motivated several of the career government officials who worked in the White House and have testified in the inquiry.

Trump also accused the top U.S. diplomat in Ukraine, Willam Taylor, of being a "Never Trumper." And on Thursday, the president sparked an uproar when he tweeted criticisms of Marie Yovanovitch, the former U.S, ambassador to Ukraine, as she testified before the House Intelligence Committee.

Contributing: Nicholas Wu