The whistleblower who filed a complaint with the intelligence community inspector general did not have direct knowledge of the communications between President Trump and the foreign leader in question.

The conversation was reportedly a July 25 phone call between Trump and Ukrainian President Volodymyr Zelensky. It is alleged that Trump urged Zelensky multiple times to work with his personal attorney Rudy Giuliani to investigate Joe Biden’s son Hunter Biden and his ties to an energy company owned by a Ukrainian oligarch. Giuliani has previously urged a top official in Ukraine to look into the ties.

An official who has been briefed on the matter, however, told CNN that the whistleblower “didn’t have direct knowledge of the communications.” The official said that the concerns and subsequent complaint came in part from the whistleblower “learning information that was not obtained during the course of their work.”

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Those details have reportedly played a role in the administration's determining that the complaint, lodged in August, didn’t fall under the reporting standards for intelligence whistleblower law.

Although many details are still unclear, the communications in question reportedly involved a “promise,” and House Democrats, as well as the elder Biden, are pushing to have the complaint and a transcript of the call between Trump and Zelensky released.

Inspector General of the Intelligence Community Michael Atkinson received the initial complaint and forwarded it to acting Director of National Intelligence Joseph Maguire, who has so far refused to pass it along to Congress.

The root of the proposed investigation into Hunter Biden stems from his being a 2014 board member for the natural gas firm Burisma Holdings. While he was still vice president, Joe Biden threatened to withhold $1 billion in U.S. loan guarantees if Ukraine did not fire its top prosecutor, who was accused of corruption and was investigating the oligarch who owned Burisma Holdings. That raised concerns of a potential conflict of interest, which could be damaging to Biden’s presidential campaign.

At the time of the prosecutor’s departure, Hunter Biden was being paid $50,000 per month for his work with the energy company. Hunter Biden left Burisma’s board earlier this year.

Both Trump and Biden have denied any wrongdoing, with Trump describing his phone call to Zelensky as “perfectly fine" and Biden saying he has never spoken to his son about his overseas business dealings.