The political nature of the now-infamous July call between President Trump and Ukrainian President Volodymyr Zelensky reportedly stuck out to an aide to Vice President Mike Pence.

Two sources familiar with the closed-door Thursday testimony of Pence aide Jennifer Williams told CNN that she found the conversation between Trump and Zelensky to be out of the ordinary because it did not have the typical tone of a diplomatic call. Williams testified that she did not bring up her concerns regarding the call with her superiors.

Williams reportedly claimed that she never heard Pence mention anything about investigations related to the 2016 election, Democratic frontrunner Joe Biden or the Ukrainian natural gas company that Biden’s son Hunter sat on the board of. Williams also mentioned that she was unaware of any request from Trump to Pence about investigations during a Sept. 1 meeting that the vice president had with Zelensky in Warsaw, according to CNN.

Although Williams’ nightly notes made note of the call and the transcript, CNN reported that she testified that she was not sure whether Pence had read the transcript.

Williams denied knowing why military aid was being withheld from Ukraine and that she was puzzled about it since she was not part of the decision-making process. However, a third source told CNN that Williams testified that she believed it was related to hearing Trump’s request that Ukraine open investigations into the Bidens and the 2016 election on the call.

Last week, Pence repeatedly refused to say whether he knew of the deal between Trump and Zelensky where nearly $400 million in military aid to Ukraine and a White House meeting was contingent on the Ukrainian government opening investigations in Biden and a conspiracy about a DNC server in Ukraine.

In the wake of the explosive testimony from career diplomat Bill Taylor last month, Pence told Fox News host Laura Ingraham that the ongoing testimonies in the impeachment inquiry only reinforce the Trump administration’s need to “drain the swamp.”

Read CNN’s report here.