'You're just scum', Republican Presidential candidates turn on each other as the race to the White House heats up

Donald Trump's rivals for the Republican presidential nomination have taken to the debate stage in Miami for the third time.

In his absence, the five ballot hopefuls are seeking a way to dislodge the former president from his commanding lead in opinion polls.

While contenders such as Florida Governor Ron DeSantis and former U.N. Ambassador Nikki Haley briefly criticised Trump, the latest episode did not appear any likelier to alter the dynamics of a race that Trump has dominated for months.

The candidates spent much of the two-hour event turning on one another as they worked to emerge as Trump's chief opponent with less than 10 weeks before the first statewide nominating contest in Iowa.

Trump opted to skip another debate, instead holding an event nearby, where he mocked the participants and demanded that the Republican Party stop "wasting time" with "unwatchable" debates.

Former U.S. President Donald Trump holds a rally in Hialeah, Florida (Getty)

DeSantis and Haley were joined by U.S. Senator Tim Scott, former New Jersey Governor Chris Christie and entrepreneur Vivek Ramaswamy and provided voters with multiple fiery exchanges.

At one point during a discussion about whether to ban TikTok, Ramaswamy took the opportunity to hit back at Haley after she criticised his use of TikTok, suggesting Haley "look after your family first", pointing out that Haley's daughter used the app.

The comment prompting Haley to warn him angrily not to mention her daughter again.

"You're just scum," she muttered.

Most of the candidates voiced support for banning TikTok, owned by a Chinese company, over national security concerns - even Ramaswamy, who has defended using the app as a way to connect with young Republican voters.

Candidates in the third Republican U.S. presidential debate in Miami, Florida (Reuters)

The debate opened with moderators asking the candidates to explain why they should be the party's standard-bearer rather than Trump, giving them a chance to make their case directly to voters watching at home.

DeSantis criticised Trump for skipping the event, which took place in their shared home state of Florida, and Haley added to the comments,

"Everybody wants to talk about President Trump. I can tell you that I think he was the right president at the right time," she said. "I don't think he's the right president now" Haley said.

Trump, 77, has done his best to deny his rivals a direct target, instead focusing on what he expects to be a rematch with Biden, 80, on Nov. 5, 2024.

Former President Donald Trump stands on stage during a rally in Florida (Getty)

As Wednesday's debate proceeded, the candidates largely avoided attacking Trump, whose still holds a lead with Republican voters despite his multiple indictments.

The candidates took aim at Democratic President Joe Biden and all pledged unconditional support for Israel and assailed Biden's handling of the crisis.

Asked what message they would send to Israeli Prime Minister Benjamin Netanyahu, DeSantis said, "I will be telling Bibi, 'Finish the job once and for all with these butchers Hamas, they're terrorists,'" using Netanyahu's nickname.

Abortion policy continues to be an issue the party is struggling to formulate a winning message on with the candidates unable to agree on how the party should best handle the complicated issue.

Candidates pose for photos at third Republican debate of the 2024 presidential campaign (Reuters)

Scott said he would support a federal 15-week ban, while Haley noted that any such legislation has essentially no chance of passing the closely divided U.S. Senate. DeSantis - who signed a six-week ban into law this year - did not address a federal law but said he stood for a "culture of life."

They will have another opportunity to try and topple Trump from the top spot on December 6, when a fourth debate will take place in Alabama.