RNA - Citing two people familiar with the matter on Tuesday, the Times said that White House lawyers had informed Trump in late August about the complaint, telling the president that they were trying to understand whether they were legally obligated to give it to Congress.
The whistleblower alleged the Republican president pressured Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden and his son Hunter, who had served as a director for Ukrainian energy company Burisma.
Trump allegedly had stalled almost $400 million in military aid and a White House visit for Zelensky to pressure Kiev into the probe. The president, however, has denied any wrongdoing.
White House Office of Management and Budget official Mark Sandy testified that he had received an email dated July 12 from the acting chief of staff's office, saying that Trump had directed the aid freeze.
According to The Times, it is unclear how many details Trump knew about the complaint when notified by White House lawyers and the White House did not immediately respond to request for comment on Tuesday evening.
The complaint from the whistleblower, a CIA officer who submitted it to the inspector general for the intelligence community in mid-August, prompted House Democrats to launch an impeachment inquiry against Trump.
The impeachment probe shifted to a public phase on November 13 after weeks of closed-door interviews in the House.
The president himself has been invited by the US House Judiciary Committee to its first impeachment hearing due next week.
Jerry Nadler, the House Judiciary Committee chairman, wrote a letter to Trump on Tuesday and invited him and his counsel to participate at the hearing scheduled for December 4.
"The Committee intends this hearing to serve as an opportunity to discuss the historical and constitutional basis of impeachment, as well as the Framers' intent and understanding of terms like 'high crimes and misdemeanors,'" Nadler said in the letter.