Republican Ron DeSantis is to announce his hotly-anticipated challenge to Donald Trump for the party's 2024 White House nomination on Wednesday, touting his ultra-conservative record as governor of Florida as a blueprint for the nation.

DeSantis is set to kick off his presidential bid during a live Twitter event with Elon Musk, the platform's mercurial owner.

"I will be interviewing Ron DeSantis and he has quite an announcement to make," Musk confirmed on Tuesday, promising the 6 pm (2200 GMT) event on Twitter spaces would be unscripted with "real time questions and answers."

"It's going to be live. Let it rip," Musk told a Wall Street Journal conference.

Long viewed as the most credible challenger to the twice-impeached Trump, DeSantis has used his platform as Florida's chief executive to burnish his conservative credentials, signing off on 80 new state laws this spring, many targeting "woke indoctrination" in schools and other public institutions.

They include a ban on the discussion of gender identity and sexual orientation in schools, a block on funding for efforts to promote diversity and inclusion at public universities and one of the most restrictive abortion laws in the country.

But the 44-year-old's official launch comes with his ratings in decline despite a slate of right-wing legislative wins in his state.

Lauded as "DeFUTURE" by The New York Post after a landslide reelection last November, DeSantis has seen expectations for a barnstorming campaign sweeping him into the Oval Office lowered in recent months.

A number of policy missteps – both domestic and on the international stage – have prompted disquiet about his readiness to take on the former president Trump, with donors worried he may have peaked too soon.

He faces the daunting task of closing an enormous polling gap, with Trump posting leads close to 40 percentage points, despite being indicted on felony financial charges and being found liable for sexual abuse in a New York civil trial. (AFP)