As Trump continues to round out his cabinet, the job of treasury secretary remains in flux, with the co-chair of Trump's transition team actively vying for the job, sources familiar with the matter told ABC News.

Howard Lutnick is looking to be tapped as treasury secretary, sources said, a move that comes as investor and hedge fund manager Scott Bessent is also a top contender for the role.

Bessent traveled to Mar-a-Lago as recently as Friday to meet with Trump about the job, the sources said.

Lutnick, on the other hand, spends hours with Trump nearly each day, presenting candidates for top roles in the administration. As such, the move by Lutnick to attempt to get a cabinet position for himself has frustrated some close to Trump.

Sources caution the job is still in flux and neither man could get the job -- with the potential for other candidates to emerge.

One potential dark horse for the job, one source told ABC News, is former Trump administration trade representative Robert Lighthizer, who Trump sees as an aggressive advocate for his tariff-heavy approach to international trade.

-ABC News' Jonathan Karl, Olivia Rubin and Katherine Faulders

President Joe Biden and Trump are meeting in the Oval Office, resuming a tradition that Trump himself flouted in 2020.

Biden spoke first and called for a smooth transition. Trump then said politics is tough but the transition will be smooth.

They did not answer questions.

Trump announced his senior staff on Wednesday, bringing back some of his well-known names from his first term and those who helped on his campaign.

Dan Scavino, one of Trump's long-time allies, was named assistant to the president and deputy chief of staff. Stephen Miller was named assistant to the president and deputy chief of staff, a move reported earlier this week.

James Blair, the Republican National Committee political director and campaign aide, has been named assistant to the president and deputy chief of staff for legislative, political and public affairs. Taylor Budowich will serve as assistant to the president and deputy chief of staff for communications and personnel. He was a senior member of several of Trump's PACs.

President-elect Donald Trump is moving quickly to install loyalists and allies into his administration. But he's struggling with making a decision on one of his top law enforcement positions: attorney general, multiple sources told ABC News.

Trump interviewed multiple candidates for attorney general on Tuesday, but he came away unsatisfied, sources with knowledge of the conversations told ABC News.

Trump interviewed Missouri Attorney General Andrew Bailey on Monday, and sat down with lawyers Jay Clayton and Bob Giuffra about the post, sources said. No final decision has been made, sources said.

Notably, billionaire Elon Musk has been involved in -- and sitting in on -- interviews with potential attorney general candidates, the sources said.

In a sign of how quickly other positions are moving, Pete Hegseth -- the Fox News host selected as the nominee for Defense Secretary -- was just called Monday and interviewed for the position Tuesday, a source familiar told ABC News.

Within hours, Trump made his choice, sources added. Several Republicans on Capitol Hill and even some Trump allies described being "caught off guard" by the pick.

-Katherine Faulders, Will Steakin, Rachel Scott, John Santucci