Sen. Richard Shelby, R-Ala., a top Republican on the Appropriations Committee, is throwing his weight behind an alternative nominee to head the Office of Management and Budget: Shalanda Young.

Young was nominated by Biden to be deputy director of the Office of Management and Budget. Young was most recently the staff director at House Appropriations, and she and Shelby have a close working relationship.

“I believe she would be good in that role. She’s smart, she knows the process inside-out, and she’s an honest broker who has demonstrated the ability to work with both sides and get things done. She would have my support, and I suspect many of my Republican colleagues would support her, as well," Shelby said in a statement. "But that’s up to the Biden Administration.”

White House press secretary Jen Psaki was asked about Shelby's support on Wednesday and the possibility of Young being a Neera Tanden replacement, but she made clear that the White House maintains support for Tanden.

-ABC News' Trish Turner

Energy and Natural Resources Committee Chairman Sen. Joe Manchin, D-W.V., will vote to confirm Rep. Deb Haaland's, D-Ariz., nomination to serve as secretary of the interior, easing concerns that Haaland's appointment could be in jeopardy.

Manchin has been in close focus on this and other nominations this week, as the moderate Democrat has significant ability to jeopardize nominees in the evenly divided Senate.

Manchin has said he will oppose the nomination of Neera Tanden to the Office of Management and Budget and has not committed to a position on Xavier Becerra's nomination to lead the Department of Health and Human Services.

"I believe that every Presidential nominee and every Member of Congress must be committed to a new era of bipartisanship. That is the standard the overwhelming majority of Americans expect and deserve," Manchin said in a statement. "With respect to Representative Haaland and her confirmation hearing, while we do not agree on every issue, she reaffirmed her strong commitment to bipartisanship, addressing the diverse needs of our country and maintaining our nation’s energy independence."

-ABC News' Allison Pecorin

Biden has officially extended the national emergency declared over the COVID-19 pandemic beyond March 1. By law, the national emergency would have ended a year after it was declared unless the president took action within 90 days of the expiration date.

"The COVID-19 pandemic continues to cause significant risk to the public health and safety of the Nation," Biden wrote in his letter to Congress. "More than 500,000 people in this Nation have perished from the disease, and it is essential to continue to combat and respond to COVID-19 with the full capacity and capability of the Federal Government."

The national emergency was initially ordered by former President Donald Trump on March 13, 2020, freeing up financial resources for the country as the pandemic took hold.

-ABC News' Molly Nagle

After an expanded detention facility for child migrants reopened in Carrizo Springs, Texas, Rep. Alexandria Ocasio-Cortez, D-N.Y., tweeted Tuesday, “This is not okay, never has been okay, never will be okay - no matter the administration or party.”

In a press briefing Wednesday, Psaki attempted to cast the Biden administration’s efforts to manage immigration as a major improvement over President Donald Trump’s policies but didn’t fully address Ocasio-Cortez's criticism that such facilities shouldn’t exist at all.

Psaki said the administration had three options when it comes to child migrants: to send them back to their countries (which she said can be dangerous), to transfer them to a facility managed by the Department of Health and Human Services, or to put them in the care of families or sponsors "without any vetting." She said the administration has chosen the middle option.

“What we are doing is working as quickly as possible to process these kids into these HHS facilities, which have been revamped, which have medical and educational services available, so that we can then transfer them to families. That's what our approach is,” Psaki said.

Psaki would not commit to a request to allow media in to prove that children are treated humanely, citing privacy and security concerns. Psaki tried to explain the administration’s options in dealing with minors at the border and why the detention facilities have become a primary strategy.

“This is a difficult situation. It's a difficult choice. That's the choice we've made,” she said.

Psaki also attempted to defend delays in transferring children from facilities run by Customs and Border Protection, which often lack amenities, to Health and Human Service facilities that are intended for longer-term care. By law, children are supposed to spend no more than 72 hours in Customs and Border Protection facilities after initial apprehension.

“There were some delays last week because of weather, and because some of these facilities to safely move these kids to, did not have power and were not in a place where they could -- they had the capacity to take in these kids and do it safely. That is not our objective. That is not our goal," Psaki said. "So some, unfortunately, did stay four days, five days, or longer, but the objective is to move them as quickly as possible to the HHS sponsored facilities.”

-ABC News' Sarah Kolinovsky