The leader of the agency responsible for approving the immunization, Dr. Stephen Hahn, maintained Sunday that the authorization was made as quickly as possible, despite claims to the contrary by President Donald Trump.

In an interview with Fox News Saturday, Trump, after seeming to take credit for the speed of the vaccine's development, said that the Food and Drug Administration could have authorized the shot for emergency use "last week."

"We do not feel that this could have been out a week earlier," Dr. Stephen Hahn, the FDA commissioner, said on ABC's "This Week." "We went through our process. We promised the American people that we would do a thorough review of the application and that's what we did. We followed our process."

Full story here.

- Adam Kelsey

New Jersey will begin giving its health care workers the COVID-19 vaccine Tuesday morning at University Hospital in Newark, the state's governor said on ABC's "This Week" Sunday.

"The first batch of 76,000, split the majority toward health care workers but a good slug toward our long-term care residents and staff, and then with each ensuing week those are the two top priorities," Gov. Phil Murphy, D-N.J., told "This Week" co-anchor Martha Raddatz.

"It'll take us a number of weeks as you can imagine to work through the entire populations in both of those groups, but it's gonna be a big day on Tuesday morning in Newark," he added.

Full story here.

- Adia Robinson

Another Cybersecurity and Infrastructure Security Administration official is stepping down at the end of the week.

Matt Masterson, a top official at CISA, who was instrumental in securing the 2020 election, confirmed on Twitter he's leaving for a position at Stanford University.

Masterson tweeted that he can't wait to work with the staff and students at Stanford.

The news comes after former CISA Director Chris Krebs was fired via tweet by President Donald Trump in November. The president bristled at Krebs' assertion that there was no evidence of fraud in the election.

Bryan Ware, another of Krebs' top lieutenants at the agency, stepped down just before his boss was fired last month.

-ABC News' Luke Barr

Sparks flew Saturday as justices on the Wisconsin Supreme Court questioned Jim Troupis, a lawyer for the Trump campaign who argued that the state should throw out 220,000 votes from Dane and Milwaukee counties.

Justice Jill Karofsky lit into Troupis under 10 minutes into the hearing, accusing the campaign of trying to disenfranchise Black voters.

“In your lawsuit, what you have done here, is you have targeted the vote of almost a quarter of a million people, a quarter of a million people not statewide in Wisconsin, but … in two of our 72 counties, two counties that are targeted because of their diverse populations, because they're urban; I presume because they vote Democratic. This lawsuit, Mr. Troupis, smacks of racism,” Karofsky said.

Troupis and the Trump campaign argued that the court should throw out four categories of votes they said did not follow state statute, including absentee ballots delivered in person at a “Get Out the Vote” event in a park, ballots applied for with a specific mail-in form, ballots missing the address of a signed witness and ballots applied for by “indefinitely confined voters.”

As the hearing continued, Justice Rebecca Dallet once again homed in on the demographic makeup of Milwaukee and Dane counties, noting that the Trump campaign was “not asking … to throw out votes in any other county.” Troupis became defensive, telling the justices that the Biden campaign could have asked for the recount to encompass the whole state.

“You made a statement, as if this was a choice based on criteria that simply are not true,” Troupis said before Dallet jumped on him.

“Who chooses which counties to ask for a recount?” Dallet asked.

Troupis responded “the candidate,” to which Dallet noted the president “had a choice when it came to the recount of which counties. … He chose to only challenge votes in the most urban, non-white, largest counties that voted overwhelmingly for Joe Biden.”

-ABC News' Alex Hosenball and Matt Mosk

Biden and Harris formally introduced newly nominated and appointed members of their administration from Wilmington, Delaware, Friday afternoon, showing off several familiar faces, be it from the Obama administration or from Capitol Hill.

For director of the White House Domestic Policy Council, a position which does not require Senate confirmation, Biden picked Susan Rice. Rice served as U.S. ambassador to the United Nations and later as national security adviser in the Obama administration.

In her remarks, Rice laid out the path of her ancestors on both sides who overcame adversity -- a paternal great grandfather who was born a slave in South Carolina and maternal grandparents who immigrated from Jamaica with no education and worked to send their children to college, leading to her mother’s role in creating the Pell Grant.

“Now at the foot of yet another bridge between crisis and opportunity, I'm honored and excited to take on this role. Joe Biden and Kamala Harris's vision for our future is expansive but achievable," Rice said, stressing her excitement to serve again and the need to develop policies that break down racial barriers that hold all Americans back.

Rep. Marcia Fudge, who has represented Ohio's 11th Congressional District for the last 12 years has been tapped for secretary of Housing and Urban Development and talked about the importance of housing in America and the need to give people hope amid  America’s ongoing crisis.

“Perhaps most importantly of all, we will help people believe once again that their government cares about them, no matter who they are. That we understand their problems, as the president-elect often recalls his father's words,” she said.

Biden's nominee for secretary of agriculture, Tom Vilsack, seemed to address some of the criticism of his previous tenure at USDA (he held the same Cabinet position he's nominated for throughout the Obama administration) by promising to deal with systemic inequities.

Vilsack also mentioned his support for Rep. Jim Clyburn's 10/20/30 plan, an effort the South Carolina congressman said aims to help counties that had a poverty level of more 20% for more than three decades. Those communities would receive at least 10% of federal funds from a specific program. When asked in 2019 if he considered the measure a form of reparations, Clyburn said the measure "absolutely" is.

Biden's pick for secretary of veterans affairs, Dennis McDonough, former President Barack Obama's White House chief of staff, pledged to make the department more inclusive to all veterans, particularly women, veterans of color and members of the LGBTQ community.

Biden's appointed Katherine Tai to U.S. trade representative, who began by recalling her parents' immigrant story of her father, a researcher at Walter Reed, and her mother, who still works at the National Institutes of Health developing treatments for opioid addictions. She also stressed the role trade can play to create opportunities and lift people out of poverty and the need to rebuild relationships around the globe.

-ABC News' Molly Nagle, John Verhovek and Beatrice Peterson