Trump 2nd term updates: Trump says USAID is run by 'radical lunatics'

According to U.S. officials, 1,000 to 1,500 additional troops are expected to be sent to the southern border, in addition to the roughly 1,500 currently there.

These additional forces will be operating under the U.S. Northern Command.

Troops have been on the border for years, and though there are only about 1,500 National Guard and reservists there now, that mission had been authorized to have up to 2,500 personnel. They serve in a support role to Homeland Security and Customs and Border Patrol along the border and do not carry out law enforcement duties.

-ABC News’ Matt Seyler

Fox News Senior White House correspondent Peter Doocy read aloud on-air the content of the letter left by former President Joe Biden to President Donald Trump.

"As I take leave of this sacred office I wish you and your family all the best in the next four years," Biden wrote, according to Fox News. "The American people -- and people around the world -- look to this house for steadiness in the inevitable storms of history, and my prayer is that in the coming years will be a time of prosperity, peace, and grace for our nation."

"May God bless you and guide you as He has blessed and guided our beloved country since our founding," Biden wrote.

Trump held up the letter for reporters on Monday night as he signed executive orders in the Oval Office. He described it to reporters on Tuesday as "very nice" and that he appreciated it.

All federal employees working on Diversity, Equity and Inclusion (DEI) programs and initiatives must be put on paid administrative leave by Wednesday at 5 p.m., according to a memo obtained by ABC News.

The decision comes as the Trump administration shuts down the relevant DEI offices and programs across the federal government.

Trump is also threatening "strong action" against DEI programs in the private sector, including possible civil compliance investigations.

House Speaker Mike Johnson posted a video on X of President Trump taking Vice President JD Vance into the Oval Office for the first time on Tuesday.

Trump can be seen walking ahead of Vance in the halls of the West Wing before showing him into the office. He introduced Vance to his communications adviser, Margo Martin, who was standing at the door to the Oval Office.

"Wow, this is pretty crazy," Vance says as Johnson narrated the video. He later said it was "incredible."

Johnson praised Vance's path to the White House, writing that "only in America can a hardworking young man from Appalachia rise from his humble circumstances to enter the Oval for first time" as vice president.