Nikki Haley, once Trump's UN ambassador, to take him on in 2024

The daughter of two Indian immigrants, Haley has gained a reputation in the Republican Party for her ability to address issues of gender and race

UN Ambassador Nikki Haley listens to US President Donald Trump in the Oval Office of the White House after it was announced the president had accepted Haley's resignation in Washington, US, O

Former South Carolina Governor Nikki Haley will launch her candidacy for the 2024 Republican presidential nomination on Feb. 15, squaring off against her one-time boss, former President Donald Trump, according to a source familiar with her plans.

Haley is expected to release details about her White House bid in an invitation to supporters later on Wednesday, according to local news outlet The Post and Courier, which first reported the planned announcement.

The daughter of two Indian immigrants who ran a successful clothing store in a rural part of the state, Haley has gained a reputation in the Republican Party for her ability to address issues of gender and race in a more credible fashion than many of her peers.

She has also pitched herself as a stalwart defender of American interests abroad, having served as U.S. ambassador to the United Nations under Trump from 2017 to 2018. During that time, the United States pulled out of the Iran nuclear deal, which was inked under Democratic President Barack Obama and was highly unpopular among Republicans.

Haley received national attention in 2015 when, as governor, she signed a bill into law removing the Confederate battle flag from the grounds of the South Carolina state capitol, following the murder of nine black churchgoers by white supremacist Dylann Roof.

If she were to win the nomination, Haley would be the first woman at the top of the Republican presidential ticket in history, as well as the party's first non-white nominee.

Among her major challenges will be nailing down a consistent message. Even in a field where most candidates have changed their mind about key issues multiple times, Haley is particularly chameleonic.

She has distanced herself from Trump several times, only to later soften her rhetoric toward the former president, saying he has an important role to play in the Republican Party.

While she has criticised Republicans for baselessly casting doubt on the results of the 2020 presidential election, she campaigned on behalf of multiple candidates who supported Trump's false election fraud claims during the 2022 midterms.

And even as she has at times adopted a conciliatory message on racial issues, she often opts for a less measured tone. In November, she said at a campaign rally that Democratic Georgia Senator Raphael Warnock, a Black man born in Savannah, should be "deported."

Playing into Haley's hands may be geography: South Carolina is historically the third state to host the Republican nominating contest, and it often plays an outsized role in the race. Haley, who governed the state from 2011 to 2017, is popular there, polls show.

While she comes into the race as an underdog - most national polls show her support in the single digits - Haley is used to running from behind, having gained a reputation in political circles for coming out on top in tough-to-win races.