President-elect Joe Biden’s incoming chief of staff, Ronald A. Klain, said Sunday that some of Biden’s first Cabinet picks will be revealed Tuesday, although he declined to say who or what positions will be announced.

Klain made the comments during an interview on ABC News’s “This Week.”

“Well, what I can confirm, George, is that you’re going to see the first of the president-elect’s Cabinet appointments on Tuesday of this week,” Klain told host George Stephanopoulos.

Klain said that by doing so, the Biden transition was “beating, in fact, the pace that was set by the Obama-Biden transition, beating the pace set by the Trump transition.”

“But if you want to know what Cabinet agencies they are and who’s going to be in those Cabinet agencies, you’ll have to wait for the president-elect to say that himself on Tuesday,” he added.

President-elect Joe Biden's newly appointed chief of staff, Ronald A. Klain, spoke to The Washington Post about the coronavirus on June 2. (The Washington Post)

Biden last week announced several senior White House staff appointments and told reporters that he has already decided on his pick to lead the Treasury Department, although he did not reveal the person’s name. Among the top candidates for the post is Federal Reserve governor Lael Brainard, who served as a senior Treasury Department official in the Obama administration.

President Trump, meanwhile, is refusing to concede the election to Biden and continues to make false accusations of widespread voter fraud.

The president and his campaign legal team have largely failed in their efforts to challenge the election in the courts. And even as most Republicans on Capitol Hill have refused to acknowledge Biden’s win, some have shifted course in recent days.

Sen. Patrick J. Toomey (R-Pa.), who is not running for reelection in 2022, said Saturday that Trump had “exhausted all plausible legal options” in Pennsylvania, after a federal judge dismissed a Trump campaign lawsuit that sought to block the certification of the state’s results.

“I congratulate President-elect Biden and Vice President-elect Kamala D. Harris on their victory,” Toomey said in a statement.

Former New Jersey governor Chris Christie (R), a Trump ally, and Sen. Kevin Cramer (R-N.D.) said Sunday that it was time for the transition to begin.

Trump weighed in on the Pennsylvania decision in a Sunday morning tweet shortly before he arrived at his golf club in Sterling, Va., for the second day in a row.

“Other than politics, how do you lose a case where large numbers of voters, far more than you need to flip Pennsylvania, are disenfranchised? Vote Observers thrown out of counting rooms,” he tweeted, even though his campaign’s attorneys have acknowledged that Republican observers were in fact granted access to polling locations.

The president also lashed out at Maryland Gov. Larry Hogan (R), who had said earlier Sunday in an appearance on CNN’s “State of the Union” that he was “embarrassed that more people in the party aren’t speaking up” against Trump.

“Well, I just don’t think there are a lot of profiles in courage, frankly,” Hogan said. “I mean, we all know how vindictive the president can be, how powerful his Twitter account is, and how he can really pressure Republicans and go after them. Very few of us are willing to stand up.”

Hours later, Trump shared a link to a report on how Hogan spent $9.46 million on coronavirus tests from South Korea that turned out to be flawed. “This RINO will never make the grade,” the president tweeted. “Hogan is just as bad as the flawed tests he paid big money for!”

Trump and some of his defenders have argued that Democrats sought to delegitimize his 2016 election by investigating his business interests and his campaign’s ties to Russia and voting to impeach him last year. Trump was later acquitted by the Senate.

Kate Bedingfield, Biden’s deputy campaign manager, on Sunday pushed back against that comparison, calling it “absurd” and “an apples-and-oranges comparison at best.”

“I don’t think that when a president gets elected that he is no longer held accountable as he moves through his administration,” Bedingfield said on “Fox News Sunday. “I think that’s an incredibly different thing.”

Trump’s efforts to “overturn the will of the American people” will fail, she added, “because, again, Joe Biden overwhelmingly won this election — 306 electoral college votes.”

“The American people voted for Joe Biden to be sworn in on January 20, 2021, and he will be,” she said.