The former South Carolina governor Nikki Haley is challenging her one-time boss for the 2024 Republican presidential nomination.
As of Tuesday morning, no other major Republican candidate beside Trump and Haley had announced bids aiming to unseat Biden, who has said he intends to seek a second four-year term.
Haley is vying to become the first female president after a poll published last week found that her entry into a 2024 Republican primary would be enough to keep Trump ahead of his only current close rival: DeSantis.
Then 38, she was also the youngest person in the US to become governor.
She was the US ambassador to the UN after Trump won the presidency in 2016, but she resigned in 2018.
The statement also noted that the abortion ban which Haley signed as governor of South Carolina contained no exceptions for rape or incest. That ban took effect, along with other similar ones in many states across the US, after the supreme court last year eliminated the right to abortion that had been established by the landmark Roe v Wade decision.
Unlike Haley, Trump faces an array of legal perils. Among other problems, those perils include a sprawling federal investigation into his attempted subversion of his defeat to Biden in 2020, his alleged incitement of the deadly January 6 Capitol attack, and his retention of classified information.
Reuters and the Associated Press contributed to this report
