A whistleblower's complaint about President Donald Trump's communications with Ukraine was hand delivered Wednesday afternoon to Capitol Hill for lawmakers to review.
Sen. Richard Burr, the Republican chairman of the Senate Intelligence Committee, said he has started to read the document but declined to give his initial thoughts.
Members of the Democratic-led House Intelligence Committee are also reviewing the documents.
The move comes just hours after the White House released a transcript of a July 25 phone call that shows the President repeatedly pressed the leader of Ukraine to investigate former Vice President Joe Biden and his son.
It also comes a day after House Speaker Nancy Pelosi declared the President had betrayed his oath of office and announced she is opening a formal impeachment inquiry.
The conversation between Trump and Ukrainian President Volodymyr Zelensky is included in the whistleblower complaint, a source familiar with the situation said last week, a revelation only raised more questions in the ongoing controversy.
Trump has downplayed the significance of the complaint, claiming the whistleblower is partisan and his conversations with foreign leaders are "appropriate."
The intelligence community inspector general last week suggested that the whistleblower complaint that triggered the Ukraine-Trump drama, raised concerns about multiple actions, sources told CNN.
However, the inspector general -- who spoke at a closed-door briefing last week -- would not say if those instances involved Trump, the sources said.
One source said that Inspector General Michael Atkinson referenced "a sequence of events" and "alleged actions" that took place. However, another source disputed that the IG provided substantive details regarding the whistleblower claim.