Rudy Giuliani tells ABC News he will not be part of President Donald Trump's legal team for the upcoming Senate impeachment trial.

“Because I gave an earlier speech [at the January 6 Trump rally before the Capitol riot],” Giuliani told ABC News Sunday night, “I am a witness and therefore unable to participate in court or Senate chamber.”

Trump was impeached by the House for the second time last week following the siege on the Capitol by a pro-Trump mob.

-ABC News' Jonathan Karl

The Delaware Humane Association hosted a virtual party with over 10,000 people to celebrate the first shelter dog moving into the White House.

While Champ and Major won't put their paws in the White House until Wednesday, the association held the fundraiser Sunday to celebrate the history being made: Major was adopted by Biden in March 2018.

"It means everything to us because it shines a light on the work we do," Delaware Humane Association's executive director Patrick Carroll said Sunday during the virtual party. "It shows that shelters are a wonderful place to adopt."

The shelter showed off photos of Major during his stay there in 2018 along with video of him and the president-elect. It also revealed dog "secretaries" which were dogs from its shelter that were selected by fans.

The Delaware Humane Association raised over $100,000, according to its host.

Biden's two German shepherds will also be the first dogs to live in the White House in four years, though Champ is no stranger to Washington. The Biden family brought the dog into their home in 2008 and he resided with them during his two terms as vice president.

The National Security Agency confirmed to ABC News that Michael Ellis has been named to be the agency’s new general counsel.

Ellis, who is considered to be a Trump loyalist, was pre-selected for the job, but his placement was slow-rolled by NSA Director Paul M. Nakasone.

Acting Defense Secretary Chris Miller demanded the NSA to put him in the career civil service job by 6 p.m. Saturday night, according to a source.

"Mr. Ellis accepted his final job offer yesterday afternoon. NSA is moving forward with his employment," an NSA spokesperson said in a statement provided to ABC News.

The Washington Post first reported the installation.

The NSA’s general counsel is a career civil service position and not an appointee position. Anyone in that post would continue on regardless of a change in administrations. They could only be removed under the same guidelines in place for other civil servants. There is a probationary period and tenure policy in place.

-ABC News' Luis Martinez

A Virginia man has been arrested near the Capitol while in possession of a gun, according to authorities.

Gordonsville resident Guy Berry, 22, was arrested at 12:15 a.m. on the 200 block of Massachusetts Avenue, the police report states. He was allegedly in possession of three high capacity magazines and 37 rounds of unregistered ammunition, police said.

Berry was charged with carrying a pistol without a license, possession of a large capacity magazine and unregistered ammunition.

-ABC News’ Jack Date

Late Friday, Health and Human Services Secretary Alex Azar refuted several media reports that he was resigning early, but did share his resignation letter -- effective Jan. 20 at noon -- on Twitter.

While Azar wrote on Twitter that it was his "duty to help ensure a smooth transition to President-elect Biden’s team during the pandemic" through Inauguration Day, he did criticize President Donald Trump and called on him to more strongly condemn the violence at the Capitol last week.

"Unfortunately, the actions and rhetoric following the election, especially during this past week, threaten to tarnish these and other historic legacies of this Administration," Azar wrote in the resignation letter. "The attacks on the Capitol were an assault on our democracy and on the tradition of peaceful transitions of power that the United States of America first brought to the world. I implore you to continue to condemn unequivocally any form of violence, to demand that no one attempt to disrupt the inaugural activities in Washington or elsewhere, and to continue to support unreservedly the peaceful and orderly transition of power on January 20, 2021."

Azar clarified he handed in the letter, dated Jan. 12, last week "along with every other political appointee."

The two-page letter, in which he calls serving as HHS secretary "the greatest professional privilege and honor of my life," details the administration's response to the coronavirus pandemic. Azar paints an entirely rosy picture, referring to it as a "remarkable response," despite skyrocketing deaths and case rates across most of the nation.

"While we mourn every lost life, our early, aggressive, and comprehensive efforts saved hundreds of thousands or even millions of American lives," he wrote, echoing a refrain from the president. There have been over 391,000 deaths in the U.S., nearly twice the number of the second-highest country (208,000 in Brazil).

He also highlighted the agency's efforts to combat the opioid crisis, electronic cigarettes and the HIV epidemic, and made special mention of "protect[ing] the sanctity of human life from conception to natural death."

Azar has served as HHS secretary since January 2018. President-elect Joe Biden has nominated Xavier Becerra, California's attorney general, to serve as his HHS chief.

ABC News' Ben Siu contributed to this report.