Trump, RFK Jr. in split-screen showdown at Libertarian National Convention

A split-screen showdown between the Republican Party's presumptive presidential nominee, Donald Trump, and independent candidate Robert F. Kennedy Jr. will occur this weekend at the Libertarian National Convention in Washington, D.C., as each hopeful seeks to court the party's base.

It's unlikely the two candidates will face off directly, however, despite calls from Kennedy for a debate between them. Kennedy addressed the convention Friday afternoon -- a day ahead of Trump's Saturday night appearance.

The Libertarian Party, which has access to the ballot in at least 37 states, is a non-interventionist political party that has seen a number of variations since its inception in the 1970s. Its members are best known for being largely socially liberal and fiscally conservative.

The party is expecting to confirm its presidential and vice presidential nominees on Sunday.

"Libertarians are some of the most independent and thoughtful thinkers in our Country ... We must all work together to help advance freedom and liberty for every American, and a second Trump Administration will achieve that goal. I look forward to speaking at the Libertarian Event, which will be attended by many of my great friends," Trump said in a statement to ABC News.

Trump and Kennedy are both looking to court voters where they can as Election Day nears. Polls show that Trump is narrowly ahead of Biden -- 41% to about 40%, respectively -- while Kennedy trails with just shy of 10%, according to 538's national polling average.

The Libertarian Party, which said they had extended speaking invitations to both Trump and Biden, called the former president's acceptance "momentous."

"This momentous occasion will mark the first time a former President directly addresses our members, candidates, and executive committee. Don't miss this opportunity to hear insights from a prominent figure in American politics and watch him engage with Libertarian ideals," the party wrote in a press release.

Kennedy later accepted a speaking slot at the convention, and then challenged Trump to a debate there, calling the venue "perfect neutral territory" for their meeting.

"You yourself have said you're not afraid to debate me as long as my poll numbers are decent... So let's meet in a couple of weeks and show the American public that at least two of the major candidates aren't afraid to debate each other," Kennedy wrote on X earlier this month.

Trump has not addressed that invite, but has separately since expressed being willing to share the debate stage with Kennedy if the latter qualified for the upcoming televised presidential debates scheduled for this summer.

Mark Rutherford, who is running to be the Libertarian Party chair, said that some Libertarians have objected to Trump and Kennedy coming to their convention, as they are not candidates of the party.

"This is the national convention for the Libertarian Party to nominate our Libertarian Party presidential and vice presidential candidate. He is the presumptive Republican nominee. It's inappropriate for him to be here speaking to it. We need to be concentrating on our own candidates," Rutherford said about Trump.

He said the same thing about Kennedy.

"Again, he's running against our candidates … So it's just not appropriate for them to be here," Rutherford said.

"[Libertarian Party leadership] are bragging about bringing these people in. I think it's confusing the public and confusing people. Why are they here at our presidential nominating convention?"

Chase Oliver, one of the Libertarian presidential candidates, called Trump and Kennedy's attendance at their convention "confusing."

"When they see Donald Trump speak with a Libertarian banner behind them, that is going to confuse our brand of the average voter ... we're gonna have to climb out of that hole and really present a real contrast, which I'm happy to do, but it would be much easier if we didn't have them on our stage," Oliver said in an interview with ABC News White House Correspondent MaryAlice Parks on Friday.

But another Libertarian delegate, Garrett Steele of Nashville, Tennessee, said that he was excited to have both Trump and Kennedy at the convention because "they've brought attention" to the party and its platform.

Oliver joins Michael Rectenwald, Mike Ter Maat, Lars Mapstead, Jacob Hornberger, Joshua Smith, Joseph Collins, Charles Ballay, Toad, Art Olivier and Jody Jones as the party's candidates at the convention.

"There's a lot of people running," said Rutherford, indicating that there was not a clear front-runner in the race.

There is a chance that Kennedy could be nominated by the delegates at the Libertarian National Convention when they vote on Sunday.

ABC News' Oren Oppenheim, Soorin Kim, Lalee Ibssa, and Kelsey Walsh contributed to this report.