One of the leading White House figures behind Donald Trump's travel ban has defended the controversial policy, saying the administration will pursue several options to reinstate the executive order.

Trump's senior policy advisor, Stephen Miller, said there had been a "judicial usurpation of power" after the Ninth Circuit Court of Appeals ruled against reinstating the measure, which temporarily suspends entry to the US for people from Iran, Iraq, Syria, Libya, Sudan, Somalia and Yemen.

Speaking on Fox News Sunday, Miller said the President will do whatever is "consistent with the law, to keep this country safe".

Here are five things you need to know about Miller, one of the most influential players in Trump's presidency.

Miller's parents were left-leaning Democrats

Trump's senior aide was the son of Democrat parents and grew up in a liberal, Jewish family in Santa Monica, California.

His beliefs changed in high school, after he read Guns, Crime and Freedom, written by the CEO of the National Rifle Association (NRA), Wayne LaPierre. Miller reportedly clashed with his school on several occasions, calling into a national radio station to denounce multiculturalism and criticise morning announcements in Spanish.

He played a leading role in Donald Trump's travel ban

Along with Steve Bannon, Trump's chief strategist and former chair of right-wing website Breitbart, Miller was involved in creating the executive order which restricted travel to the US from several Muslim-majority countries.

Miller accused Maya Angelou of having "racial paranoia"

While studying at Duke University, Miller produced a series of conservative newspaper articles on race, immigration and women's rights, solidifying his reputation as a right-wing firebrand. On one occasion, he accused poet Maya Angelou of "racial paranoia" – arguing the university administration was "so obsessed with multiculturalism (aka segregation)."

He also described a Chicano student organisation – which summarised itself as "founded on the principles of self-determination for the liberation of our people" – as a "radical national Hispanic group that believes in racial superiority".

He worked for Jeff Sessions

Miller was formerly the communications director for Attorney General Jeff Sessions, the former Alabama Senator and Republican critic of free-trade deals and illegal immigration. Sessions, who was forced to defend a career blighted by allegations of racism and bigotry in a confirmation hearing earlier this month, was confirmed as Trump's Attorney General in February.

He was involved in reporting the 2006 Duke lacrosse scandal

During his time at Duke, he wrote for the student newspaper about a 2006 case in which a black woman working as a dancer accused three white students of rape. Miller argued innocent athletes had been presumed guilty and treated unfairly, focusing on the issue of race. Eventually, the charges against the lacrosse players were dropped.

He wrote that the case "provided a fantastic opportunity to advance a social agenda and to keep the distance between the paranoid delusions of widespread racism upon which so many of the careers and the lives of the activists have been built and the rather obvious reality that the overwhelming majority of whites in America are not racist."

Stephen Miller
Stephen Miller is a White House senior advisor Andrew Harrer - Pool/Getty Images