Nikki Haley, a former South Carolina governor and United Nations ambassador, has announced she is a candidate to become US president in 2024.
“Now is not the time to hold back. Now is the time for a strong and proud America,” she tweeted, linking to a campaign video.
She is the second major Republican candidate to run, after ex-boss Donald Trump launched his bid in November.
Ms Haley is the third Indian American to seek a presidential nomination.
The former governor, 51, said in 2021 that she wouldn’t challenge Mr Trump for the White House. But she changed her position in recent months, citing the need for “generational change”.
Other Republicans expected to launch campaigns to be selected by their party include Florida Governor Ron DeSantis and former Vice-President Mike Pence.
Ms Haley has previously criticised Mr Trump’s behaviour up to and during the 6 January 2021 attack on the US Capitol by his supporters.
The day after the riot, she said in a speech that “his actions since election day will be judged harshly by history”.
Most early polls show Mr Trump with a comfortable lead in South Carolina, whose primary he won on his way to the presidency in 2016 – an indication of the uphill battle the former ambassador will have, even on what should be friendly ground. (BBC)