The US Senate confirmed Jeff Sessions as the next attorney general, following a bitter debate in the chamber that saw Republicans formally rebuke Senator Elizabeth Warren for the manner in which she criticised her colleague from Alabama.
Sessions, a four-term US senator, was the first senator to endorse Trump in February 2016, and his conservative, populist views have shaped many of the Administration's early policies, including on immigration.
The vote, 52-47 in favour of confirmation, ran largely down party lines.
Republicans accused Democrats of seeking to undercut Trump by attempting to derail his Cabinet choices. "It's no secret that our Democrat colleagues don't like the new president and are doing what they can to undermine the new administration," said Senator Chuck Grassley, the Judiciary Committee chairman.
He expressed disappointment in colleagues who, he said, suggested Sessions won't be able to put aside his policy preferences and enforce the law. "This is especially troubling after he specifically committed to us during his confirmation hearing that, if he's confirmed, he will follow the law, regardless of whether he supported the statute as a policy matter," Grassley said.