Vindman said in his remarks that after he raised his objections, Fiona Hill, who was a Trump adviser on Russia at the time, entered the room and told Sondland his statements were inappropriate.

According to NBC News, Hill told House investigators that she entered the room as Perry was leaving. That account was confirmed to POLITICO.

That timeline would put Perry in the meeting when Vindman raised his objections about Sondland's request that Ukrainian officials investigate the Bidens — which Perry has repeatedly denied.

"Not once, as God is my witness, not once was a Biden name — not the former vice president, not his son — ever mentioned," Perry told the CBN News on Oct. 7. He repeated those denials in a Fox News radio interview last week.

A DOE spokesperson said Perry stands by his earlier statement but did not comment on the July 10 meeting.

Perry, who plans to step down from office on December 1, refused earlier this month to comply with congressional subpoenas seeking information on meetings and phone calls he took part in involving Ukraine officials.

Fiona Hill, a former adviser to President Donald Trump on Russia. | Evan Vucci/AP Photo

The July 10 briefing where Vindman said he raised his objections came shortly after a separate meeting at the White House that day. That meeting was abruptly halted by then-national security adviser John Bolton after Sondland began discussing Ukraine conducting specific investigations in order to secure a meeting between Ukrainian President Volodymyr Zelensky and Trump.

Sondland has said that he, Perry and former U.S. special representative for Ukraine Kurt Volker were the "three amigos" on Ukraine outreach for the administration.

But some Democrats have begun to question whether Sondland, a Republican donor, perjured himself during his closed-door testimony to impeachment investigators earlier this month.

Democratic lawmakers have also said they also want to review allegations that Perry pressured Ukraine officials to fire from the advisory board of the country’s state-owned natural gas company Amos Hochstein, a former Biden aide and State Department energy official who is also an executive at a U.S. LNG company.

Perry pushed two Houston oil and gas executives to take Hochstein’s place, sources said earlier, although Perry has said he only offered the two men as potential advisers to the company.

Vindman’s testimony before the three House committees spearheading the impeachment inquiry marked the most significant crack yet in the White House’s blockade of witness testimony. His remarks referred to efforts by “outside influencers” to promote “a false narrative of Ukraine inconsistent with the consensus views of the interagency.”

Rudy Giuliani, Trump’s personal attorney was directing that shadow campaign, which led to the ouster of Marie Yovanovitch as the U.S. ambassador to Ukraine. Vindman did not name Giuliani in his opening statement, but wrote he was alarmed that such efforts were inconsistent with American foreign policy and harming U.S.-Ukraine relations.