Biden's pick for secretary of housing and urban development, Rep. Marcia Fudge, D.-Ohio, and his choice to lead the Council of Economic Advisers, Cecilia Rouse, testified before Senate Committee on Banking, Housing and Urban Development for a joint confirmation hearing Thursday morning.

Fudge emphasized her commitment to expanding accessible housing for Americans, if confirmed, and highlighted the housing crisis created by the COVID-19 pandemic.

"We need policies and programs that can adapt to meet your unique housing challenges, and I would very much like to work with each of you to find the right answers for your states," Fudge said. "It bears mentioning, particularly in this moment of crisis that HUD, perhaps more than any other department, exists to serve the most vulnerable people in America. That mandate matters a great deal to me."

She faced scrutiny from some Republican senators about past statements and tweets critical of the GOP, but Fudge pushed back and maintained that she would commit to working with Republicans, as she said she's done in the House.

Rouse, who Biden nominated to lead the Council of Economic Advisers, also discussed her commitment to bolstering the American economy.

"We must take action to shepherd our nation's economy back onto solid footing," Rouse said. "But as deeply distressing as this pandemic and economic fallout have been, it is also an opportunity to rebuild the economy better than it was before, making it work for everyone by increasing the availability of fulfilling jobs and leaving no one vulnerable to falling through the cracks."

House Speaker Nancy Pelosi told reporters Thursday that she is concerned about threats against members of Congress in the wake of the Capitol attack and that the "enemy is within the House of Representatives."

"We will probably need a supplemental for more security for members when the enemy is within the House of Representatives," Pelosi said, asked about what's being done to help members feel safe and about a demand by more than 30 House members to use their congressional allowances for personal safety in their home districts.

When asked to expand on what she meant by "enemy within" she responded, "We have members of Congress who want to bring guns on the floor and have threatened violence on other members of Congress."

Her comments come after some Republicans have tried, in recent days, to bring their guns on the House floor, despite guns being forbidden there and the addition of a metal detector at the chamber door.

-ABC News' Mariam Khan

House Minority Leader Kevin McCarthy is traveling to Mar-a-Lago Thursday to meet with former President Donald Trump amid Republican Party infighting in the wake of the Jan. 6 attack on the Capitol and Trump's second impeachment.

On Wednesday, McCarthy implored GOP colleagues on a conference call to stop attacking each other and to focus on countering the agenda from Democrats and Biden, a person familiar with his remarks confirmed to ABC News.

"Cut that crap out," he said of the intraparty attacks. “If you’re not focused on what you’re doing and what the Democrats are doing wrong, and you’re focused on talking about one another, I’m not putting up with that anymore.”

Some conservatives are threatening to back a primary challenger against No. 3 House Republican Liz Cheney, R-Wyo., and nine other Republicans who backed Trump's impeachment. Rep. Matt Gaetz, R-Fla., is traveling to Wyoming Thursday to rally against her, and other far-right members of the conference want her removed from party leadership.

McCarthy is expected to confront the issue at a conference meeting next week, as he also works to mend his relationship with Trump. Although McCarthy did not join the 10 House Republicans who voted to impeach Trump, he said in his floor remarks at the time, “The president bears responsibility for Wednesday’s attack on Congress by mob rioters.”

-ABC News' Katherine Faulders and Benjamin Siegel

In line with the priorities of the Biden administration, Senate Majority Leader Chuck Schumer in his floor remarks Thursday said Democrats will begin moving forward on COVID-19 relief next week -- with or without their Republican colleagues.

"If our Republican colleagues decide to oppose this urgent and necessary legislation we will have to move forward with out them," Schumer said. "We have a responsibility to help the American people fast. The Senate will begin that work next week."

Schumer said earlier this week that Democrats should be prepared to vote on a budget resolution next week -- the first step on moving forward with budget reconciliation, which could allow Democrats to pass some COVID-19 priorities without Republican support.

"The dangers of undershooting our response are far greater than overshooting," Schumer added.

-ABC News' Allison Pecorin