Trump-Biden transition: Attorney Sidney Powell back at White House Sunday

Asked whether he will join with other House Republicans to formally object to the certification of the Electoral College results on Jan. 6, House Minority Leader Kevin McCarthy, R-Calif., laughed and told reporters, "We'll watch and see," per the pool reporter on Capitol Hill. 

McCarthy hasn't formally taken a position on the long-shot effort, which still lacks Senate Republican support needed to force debate and vote on the results of the election, nor has he recognized Biden as the president-elect.

The Electoral College affirmed Biden's victory on Monday without any faithless electors. Trump won 232 electoral votes to Biden's 306.

-ABC News' Benjamin Siegel

White House deputy press secretary Brian Morgenstern told reporters Friday that the president remains willing to take the COVID-19 vaccine when the time is right, while noting that Trump has already been infected with the virus. 

When asked directly if there are concerns about him being vaccinated too close to receiving the monoclonal antibody cocktail, as the Centers for Disease Control and Prevention recommends waiting 90 days between the two, Morgenstern said, "I don't know about concerns." But he added Trump is "perfectly willing to get it, and if the advice is that it is fine -- it will be effective if he takes it sooner rather than later -- he'll do that."

The response comes ahead of Biden being slated to receive the first dose of Pfizer's vaccine on Monday and following Vice President Mike Pence's public vaccination Friday morning.

Morgenstern was also asked to explain why the public has not heard from Trump all week.

"There's a lot of work that goes on that isn't necessarily public, but he is hard at work, and when it's the appropriate time for him to come speak publicly, of course that's his right, his prerogative to do," he said. "But at this point the administration continues to work very hard behind the scenes, and to the extent we have to speak publicly we do that. But the work is being done whether or not he's coming in front of you."

-ABC News' Elizabeth Thomas

The Biden transition team is pushing back on Acting Secretary of Defense Chris Miller's statement earlier Friday that there was a "mutually agreed upon holiday break" between the Pentagon and Biden officials, stressing the Biden team felt it was important to keep conversations going over the holiday.

Miller had denied reporting earlier in the day that there had been a halt to transition meetings with the Biden team, saying, "After the mutually-agreed upon holiday pause, which begins tomorrow, we will continue with the transition and rescheduled meetings from today."

However, the Biden transition disputed Miller's claim on a call briefing reporters Friday afternoon.

"Let me be clear: There was no mutually agreed upon holiday break. In fact, we think it's important that briefings and other engagements continue during this period, as there's no time to spare, and that's particularly true in the aftermath of the ascertainment delay," said transition official Yohannes Abraham.

Abraham added it was the team's expectation that meetings would continue "immediately."

Biden's team did not answer when asked if Miller was lying in his statement, instead saying the press could make its own judgments based on the information provided.

-ABC News' Molly Nagle and Luis Martinez

Incoming Biden-Harris national economic adviser Brian Deese released a statement on congressional relief negotiations Friday warning against "unnecessary provisions" that might hamper efforts on the Hill.

"While we are encouraged by the bipartisan effort underway to provide critical relief to millions of Americas, the package should not include unnecessary provisions that would hamper the Treasury Department and the Federal Reserve’s ability to fight economic crises," Deese said.

A Democratic aide told ABC News earlier Friday a relief deal was in sight -- "until Sen. Toomey and Republicans inserted an 11th hour purely political, unrelated provision to tie Biden’s hands and risk throwing the economy into a tailspin."

"The Toomey provision would be an unprecedented change to the law to strip the Fed chair of one of their most important tools to quickly respond to any future economic crisis," the aide said.

The $900 billion package currently on the negotiating table -- the largest package in history behind the relief bill passed in March -- is expected to include additional funding on expanded federal unemployment benefits and stimulus checks to millions of Americans below a certain income level.

With government funding set to expire at midnight, negotiators are working to strike deals on both government spending and COVID-19 relief in order to avoid a government shutdown.