U.S. Attorney General nominee William Barr arrives for a meeting with Senate Judiciary Committee member Sen. Lindsay Graham (R-SC) in his office in the Russell Senate Office Building on Capitol Hill January 09, 2019 in Washington, DC. (Photo by Chip Somodevilla/Getty Images)

(CNSNews.com) - "On my watch, Bob will be allowed to finish his work," Attorney General-nominee William Barr told his confirmation hearing on Tuesday. He was talking about Special Counsel Robert Mueller's ongoing Trump-Russia probe.

"President Trump has sought no assurances, promises or commitments from me of any kind, either express or implied, and I have not given him any other than that I would run the department with professionalism and integrity," Barr said in his opening statement.

"As attorney-general, my allegiance will be to the rule of law, the Constitution and the American people. This is how it should be, this is how it must be, and if you confirm me, this is how it will be."

Anticipating certain questions from the committee, Barr said he believes it is "vitally important" that the special counsel be allowed to complete his investigation.

I have known Bob Mueller for 30 years. We worked closely together throughout my previous tenure at the Department of Justice. We've been friends since. And I have the utmost respect for Bob and his distinguished record of public service. And when he was named special counsel, I said his selection was good news and that knowing him, I had confidence he would handle the matter properly. And I still have that same confidence today. Given his public actions to date, I expect that the special counsel is well along in his investigation. At the same time, the president has been steadfast that he was not involved in any collusion with Russian attempts to interfere in the election. I believe it is in the best interests of everyone -- the president, Congress and the American people -- that this matter be resolved by allowing the special counsel to complete his work. The country needs a credible resolution to these issues. And if confirmed, I will not permit partisan politics, personal interests, or any other improper consideration to interfere with this or any other investigation. I will follow the special counsel regulations scrupulously and in good faith, and on my watch, Bob will be allowed to finish his work.

Barr said he believes it is "very important" for the public and the Congress to be informed of the results of Mueller's long probe. "My goal will be to provide as much transparency as I can consistent with the law."

Referring to the 19-page memorandum he wrote last June, Barr said his memo was intended to give other lawyers "the benefit of my view." He said the memo was a "narrow" expression of his thinking on a specific obstruction-of-justice theory under a single statute that he thought Mueller might be considering.

"The memo did not address, or in any other way, question the special counsel's core investigation into Russian efforts to interfere in the election," Barr said. "Nor did it address other potential obstruction-of-justice theories or argue, as some have wrongly suggested, that a president can never obstruct justice."

Barr said as attorney general, his priorities will be fighting violent crime, both "predatory violence" and crimes motivated by bias; "enforcing and improving our immigration laws" (he called for secure borders and processing and removing those who unlawfully enter); and ensuring that the right to vote is fully protected and that elections are free from interference.