President Donald Trump bashed Jennifer Williams, Vice President Mike Pence’s national security adviser and a witness in the impeachment investigation, on Sunday by claiming without evidence that she was a “Never Trumper”

“Tell Jennifer Williams, whoever that is, to read BOTH transcripts of the presidential calls, & see the just released ststement [sic] from Ukraine,” Trump tweeted. “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!”

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

Trump’s tweet was a response to Williams’ closed-door testimony, the transcript of which was released by the House Intelligence Committee on Saturday.

The transcript shows that Williams, who was on the infamous call between Trump and Ukrainian President Volodymyr Zelensky in July, told impeachment investigators she heard Zelensky mention Burisma, a Ukrainian gas company with ties to Joe Biden’s son Hunter, during the call.

Williams’ account contradicts the White House’s released memo on the call, which does not record Zelensky bringing up Burisma. During the call, Trump had asked Zelensky to do him a “favor” and open an investigation into Biden as they were discussing U.S. military aid to Ukraine.

Williams also described the call as “unusual and inappropriate.”

Trump has baselessly accused other witnesses in the impeachment investigation, such as Bill Taylor and Lt. Col. Alexander Vindman, of being “Never Trumpers” in an effort to discredit their testimonies on his scheme.