Williams also told investigators that she put a hard copy of the call transcript in Pence’s briefing book, but did not know whether he had read it.

The July 25 phone call is at the center of House Democrats’ impeachment inquiry, as lawmakers also examine whether Trump sought to condition nearly $400 million in military aid on a public commitment by Ukraine to pursue investigations targeting former Vice President Joe Biden, among others.

The impeachment inquiry also focuses on whether Trump sought to use a White House meeting with Zelensky and other events as leverage to pressure the Ukrainian president to publicly commit to Trump’s desired investigations.

Williams testified she was told that Trump asked Pence not to attend Zelensky’s inauguration in May — a month after initially asking the vice president to travel to Kyiv for the event. She added that she was never given an explanation for the reversal.

Williams first-hand account details a White House and a U.S. national security apparatus deeply troubled about what appeared to be an inexplicable reversal of the Trump administration’s posture toward Ukraine, a U.S. strategic ally subject to Moscow’s malign influence in the region. And her testimony will likely add more weight to Democrats’ case that Trump’s Ukraine pressure campaign was motivated by his personal political interests — rather than a desire to root out corruption, as the president and his allies have argued.

In her hand-written notes, Williams jotted down that Zelensky specifically mentioned Burisma, the Ukrainian energy company where Biden’s son, Hunter, was a board member. But a summary of the call put out by the White House makes no mention of Burisma.

Williams initially testified that Trump mentioned Burisma on the call, but she amended her testimony last week to reflect that it was Zelensky, not Trump, who mentioned the company.

Lt. Col. Alexander Vindman, an Army officer and Ukraine specialist on the National Security Council staff, also told investigators he recalled Zelensky specifically mention the energy company. He flagged the discrepancies in the White House’s memo and suggested several edits, some of which he described as “significant.” He said those changes were never included in the final version that was made public.