The phone call between President Donald Trump and his Ukrainian counterpart at the center of Congress’ impeachment investigation was “inappropriate,” an aide to Vice President Mike Pence told lawmakers, according to a transcript released on Saturday.

Jennifer Williams, a foreign policy aide to Pence who was listening to the call on July 25, testified that Trump’s insistence that Ukraine carry out politically sensitive investigations “struck me as unusual and inappropriate.”

She said the discussion was “more political in nature” than phone calls with other foreign leaders, and included what she viewed as specific references to the president’s “personal political agenda.”

Trump’s call — which he has repeatedly termed “perfect” — is at the heart of the Democratic-led inquiry into whether the Republican president misused US foreign policy to undermine former Vice President Joe Biden, one of his potential opponents in the 2020 election.

The House of Representatives on Saturday also released a transcript of an earlier closed-door deposition by Tim Morrison, a former White House aide with the National Security Council focusing on Europe and Russia policy, who was also on the call.

Morrison, who resigned a day before his deposition last month, and Williams both expressed concerns about Trump’s remarks to Ukrainian President Volodymyr Zelenskiy. Williams and Morrison are scheduled to testify publicly next week.

“I was not comfortable with any idea that President Zelenskiy should allow himself to be involved in our politics,” Morrison told lawmakers. He also said found Zelenskiy’s tone in the call with Trump to be “obsequious.”

Morrison declined to say he thought the call was illegal or improper, stressing instead that he thought it would leak, damaging relations with Ukraine. He said he only learned later that the aid to Ukraine was conditioned on the investigations.