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

Former New Jersey governor and ABC News political contributor Chris Christie, criticized President Donald Trump and his allies' efforts to overturn President-elect Joe Biden's election victory during "This Week"'s Powerhouse Players Roundtable discussion on Sunday.

"The legal theory put forward by his legal team and by the president is an absurdity," Christie said. "The reason why the Supreme Court didn't take it is because it's an absurd idea to think that any state or any number of states, no matter how good they are, can challenge another state's right to run the election as they see fit. And, also, there's no evidence," he added.

Christie also denounced what he called were "attacks" by the president on "decent Republican governors."

"What's gotten even worse ... is the attacks by the president on good, hardworking, decent Republican governors," he said. "He's calling them corrupt, and also telling people things that aren't true," Christie said, mentioning the president's recent comments about Arizona Gov. Doug Ducey and Georgia Gov. Brian Kemp.

The president tweeted in November that Kemp was "hapless" and should "overrule his obstinate secretary of state," Brad Raffensperger -- also a Republican backer of Trump -- after the latter has refused to intervene to help Trump.

"The governor's done nothing," Trump also said in a Fox News interview. "He's done absolutely nothing. I'm ashamed that I endorsed him."

On Dec. 12, the president tweeted, "Who is a worse governor, @BrianKempGA of Georgia or @dougducey of Arizona???" as part of a series of tweets blasting both governors since the presidential election.