President-elect Donald Trump is expected to announce that Stephen Miller, an immigration hard-liner and one of his senior advisers, will become his deputy chief of staff for policy, multiple sources familiar with the matter told ABC News.

During Trump’s first term, Miller, 38, was known as the mastermind of the Muslim travel ban, the brutal family separation policy at the U.S.-Mexico border, and other policies defined by their rigid nativist approach.

Stephen Miller will return to the White House to serve as deputy chief of staff for policy for President-elect Donald

A longtime adviser to Trump, Miller began working for the then-candidate as a speechwriter in his 2016 presidential campaign. He later became a senior adviser in Trump’s first presidential administration and was involved in many of his hardline immigration policies,

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 team's plans said Monday.

Sources also anticipate Miller will work closely with Thomas D. Homan in overseeing immigration policy. Trump named Homan, the former acting director of Immigration and Customs Enforcement, as his “border czar” on Sunday.

President-elect Donald Trump on Monday named longtime immigration adviser Stephen Miller as his incoming deputy chief of staff for policy.

Scavino will return to the White House as an assistant to the president and deputy chief of staff. He was the director of social media for the Trump 2016 presidential campaign and

President-elect Trump announced Wednesday that four senior advisers from his campaign will join him at the White House when he takes office in January. Dan Scavino, Stephen Miller, James Blair and Taylor Budowich will all take senior staff roles in the White House,