First pardoned Jan. 6 rioters released in DC

Among executive orders signed by Trump at the Oval Office is one ending birthright citizenship.

Such a move, though, is expected to face significant legal hurdles. Under the 14th Amendment to the Constitution, any person born within the territory of the U.S. is a U.S. citizen.

When a reporter pointed out that that order will likely be challenged, Trump said, "You could be right."

"We have good grounds," he added.

While signing a slew of executive orders from the Oval Office on Monday night, Trump found a letter that outgoing President Joe Biden had left for him inside the Resolute desk.

Trump found it after Fox News' Peter Doocy asked if he'd been left a letter from Biden.

After joking about reading it aloud to the press, Trump said he would read it privately first.

Trump, surrounded by executive orders he planned to sign Monday evening, also signed an order pardoning approximately 1,500 Jan. 6 rioters.

The order also includes six commutations, he said. Though the text of the pardon actually includes 14 commutations.

"We hope they come out tonight. Frankly, they're expecting it," Trump told reporters.

As of early January, more than 1,580 individuals have been charged criminally in federal court in connection with Jan. 6, with over 1,000 pleading guilty, according to the Department of Justice.

Trump returned to the Oval Office to sign more executive orders at the Resolute desk, including one declaring a national emergency at the southern border.