The super PAC backing Robert F. Kennedy Jr.'s presidential bid, American Values 2024, announced a glitzy fundraiser gala for late January that touted Martin Sheen, who played the U.S. president on "West Wing," former boxer Mike Tyson, and singers Dionne Warwick and Andrea Bocelli as guests.

American Values promoted the event last week by sharing it on X, previously known as Twitter, and the Daily Mail reported the appearance of all four stars at the gala. CBS News obtained a copy of the invitation, and although it didn't include the names of the artists, the super PAC confirmed the report.

But soon after the PAC's social media post appeared, Sheen said in an Instagram story, "I do not endorse RFK Jr. nor I will I be attending his party." Sheen, who played fictional President and former New Hampshire Gov. Josiah Bartlett in the award-winning show, added that he's "whole heartedly supporting Joe Biden and the Democratic ticket for 2024."

The fundraiser, hosted by American Values 2024 and another PAC supporting Kennedy, will celebrate the independent candidate's 70th birthday at a gala scheduled for the eve of the New Hampshire primary, on Jan. 22, in Indian Wells, California.

Bradley Whitford, who played Sheen's White House deputy chief of staff in the TV series, reiterated on X that Sheen is not supporting Kennedy.

"There's a story going around saying that Martin Sheen is supporting @RobertKennedyJr for president. The story is incorrect," Whitford said on X. 

Warwick called the PAC's announcement "absolutely ridiculous" and said she was unaware of the event. 

"I don't know anything about this event. I did not agree to it and I certainly won't be there," Warwick said on X. "If you are going to lie on my name, at least lie about something cool," she added. 

A representative for Bocelli told Rolling Stone he is not performing at the gala and that he won't even be in the U.S. this month. 

In a statement sent to CBS News, the Kennedy campaign says it does not have "anything to do with organizing this event."

"The campaign has no knowledge of who is attending and can't confirm or deny anyone's participation, either as entertainment or as a guest," Kennedy press secretary Stefanie Spear told CBS News.

American Values 2024 has not responded to a request for comment. 

It's not yet known whether actor and former boxer Mike Tyson will be attending the event. 

Cristina Corujo is a digital journalist covering politics at CBS News. Cristina previously worked at ABC News Digital producing video content and writing stories for its website. Her work can also be found in the Washington Post, NBC and NY1.