President-elect Donald Trump is expected to name Stephen Miller as his deputy chief of staff for policy at the White House, a source with knowledge of the transition teams plans said Monday, NBC News reports.

While Trump hasnt made his choice public yet, Vice President-elect JD Vance appeared to confirm the news in a post on X as he reacted to CNNs report about Miller being chosen for the role.

This is another fantastic pick by the president. Congrats @StephenM! Vance said.

NBC News has reached out to the Trump team for comment. Trump has named campaign manager Susie Wiles as his White House chief of staff.

Miller, a staunch hard-liner on immigration policy, worked in the White House during Trumps first term in office, serving both as director of speechwriting and as a senior adviser to the president.

For years, Miller has advocated a hard-right policy on immigration. Before Trump lost to President Joe Biden in 2020, Miller had previewed plans to ramp up an even more restrictive immigration agenda. He told NBC News at the time that a second Trump term would prioritize limiting asylum grants and work visas, punishing and outlawing “sanctuary cities,” and expanding the travel ban with tougher screening for visa applicants.

He likely would be instrumental next year in attempting to execute Trump’s promise to force mass deportations of undocumented immigrants.

On Election Day last week, Miller wrote in a post on X, “GET THE HELL TO THE POLLS AND VOTE TO END THE INVASION!!!” He wrote in another post that day, “Illegals are raping and murdering American children. All the men of America need to fulfill their duty, get to the voting booth, and end the invasion once and for all.

Miller in May criticized the Senate immigration bill that Republicans shut down following pressure from Trump, saying, When Democrats say border security they mean more efficiently processing illegals for ENTRY to America. Actual border security means DEPORTATION—which Biden has shut down by executive fiat. Deportations have continued under the Biden administration.

Since leaving the White House, he has run the group America First Legal, which he founded with former Trump chief of staff Mark Meadows.

In 2021, the group sued the Biden administration, claiming that the president’s American Rescue Plan discriminated against white farmers. The organization has also filed multiple complaints with the U.S. Equal Employment Opportunity Commission, such as one submitted last year to investigate what it called “woke” programs at the Kellogg Co.

And while Trump tried to distance himself during the 2024 campaign from Project 2025, Millers group was one of the more than 100 conservative organizations that formally backed the initiative. Democrats and Vice President Kamala Harris campaign warned about what they said Project 2025 would mean for the nation, including cuts to programs that combat climate change, the elimination of the Department of Education and further limits on access to abortion.

In 2021, the group sued the Biden administration, claiming that the president’s American Rescue Plan discriminated against white farmers. The organization has also filed multiple complaints with the U.S. Equal Employment Opportunity Commission, such as one submitted last year to investigate what it called “woke” programs at the Kellogg Co.

And while Trump tried to distance himself during the 2024 campaign from Project 2025, Millers group was one of the more than 100 conservative organizations that formally backed the initiative. Democrats and Vice President Kamala Harris campaign warned about what they said Project 2025 would mean for the nation, including cuts to programs that combat climate change, the elimination of the Department of Education and further limits on access to abortion.

In the days before the election, Robert F. Kennedy Jr. told NBC News that he ran into Miller at Trumps rally at Madison Square Garden and said Miller told him that the former president was committed to Kennedys Make America Healthy Again agenda.

He said to me, ‘I want you to know something — that literally everybody on this staff, from top to bottom, is committed to MAHA, and we’re so excited about getting micro-plastics out of our bodies, and our food, about getting the pesticides off of our agricultural fields, about getting the chemicals and the food colorings out of our food,' Kennedy told NBC. And he said, ‘I’m convinced that if you get — if we get in there and you are allowed to do what you’re going to do, which President Trump is gonna make sure it happens, that we’ll be able to reduce chronic disease in this country by half within four years.’

This story first appeared on NBCNews.com. More from NBC News:

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