Former Attorney General Jeff Sessions, who Trump effectively fired in November, had recused from overseeing the Russian Federation investigation.
"At no time has the White House asked for nor have I provided any promises or commitments concerning the special counsel investigation or any other investigation", Whitaker said in his opening remarks.
Democratic Rep. Pramila Jayapal (Wash.) said Friday that the United States government should pay reparations to be made to migrant kids who had been separated from their families at the border. They were voted down every time, vastly outnumbered by Democrats.
Whitaker testified following a lengthy fight with Nadler over the prospect that he would be subpoenaed for not answering questions.
Whitaker testified that he has not discussed the probe with President Donald Trump nor denied funding for it, as Democrats pressed him on everything from his conversations with the President and other White House officials to his decision not to recuse himself from special counsel Robert Mueller's investigation. "I will behave appropriately as a member of the Judiciary Committee".More news: Larry Sabato Discusses Democratic Party, Justin Fairfax Following 2nd Allegation
Nadler said the hearing was crucial for lawmakers to get answers to questions about Whitaker's role at the Department of Justice and his appointment.
The hearing was hugely confrontational, as Democrat after Democrat grilled Whitaker over his ascension to acting attorney general, his conversations about the ongoing investigation and his past comments as a private citizen about Mueller and the probe. "As part of that work, I fully intend to call you back for an interview, under subpoena if necessary, and I expect more fulsome answers at that time".
During a testy exchange with Democratic Judiciary Committee Chairman Jerry Nadler, Mr Whitaker at one point responded: "Mr Chairman, it appears that your five minutes is up", triggering tense laughter in the chamber. The question that this Committee must now ask is: "Why?"
Trump's nominee to permanently take over as attorney general, William Barr, could be confirmed by the Senate as early as next week after a Senate panel voted to advance him Thursday, reported CNN. "I have and will continue to manage this investigation in a manner that is consistent with the governing regulations".
Whitaker had threatened not to show up to the hearing after Democrats approved a subpoena if he didn't answer all their questions, but the committee chairman dropped the threat Thursday night.More news: Rare snow blankets Seattle, canceling flights and wreaking havoc
"Mr. Chairman, I see that your five minutes is up", Whitaker said.
Republican Representative Debbie Lesko of Arizona called the entire hearing "nothing but character assassination and harassment of our witness".
Later, he was scolded by Rep. Sheila Jackson Lee, D-Texas, when she asked if her time had been restored and Whitaker responded: "I don't know if your time's been restored or not".
Democrats said they would inquire about Whitaker's past business dealings, too. Jerrold Nadler's (D-N.Y.) line of questioning. "Have you communicated any information in that briefing to President Trump?".
Before he became Sessions' Chief of Staff, Whitaker argued Mueller was close to overstepping his boundaries.More news: House Democrats Divided On Strategy To Force Release Of Trump's Tax Returns
The Russia investigation into Trump campaign ties and possible obstruction of justice has been highly politicised since Mr Trump's firing of FBI Director James Comey in May 2017.