Washington (CNN) -- Organizers for Saturday's tea party rally in Iowa Tuesday blamed an internal miscommunication over the event's schedule for rescinding a speaking slot Tuesday for former Republican Senate candidate Christine O'Donnell.
The group had confirmed Monday that O'Donnell would speak. She would have been prior to the keynote from Sarah Palin which had raised the specter of the two on the same stage.
Ken Crow, founder of the Tea Party of America, said initially he was "under the assumption we had an open slot" after her supporters had inquired Monday about whether she could speak.
O'Donnell is on a national speaking tour for her book, "Troublemaker."
After the request for her to appear at the event was made to a fellow organizer, Crow looked at the speaking agenda and thought there was space for her. She was informed Monday she could speak, event co-organizer Charlie Gruschow told CNN Monday night.
Tuesday morning it was determined there was not enough time for her, Crow said.
"It was a schedule screw-up on my part," an apologetic Crow told CNN. "It is my fault."
Crow insisted the decision did not have anything to do with O'Donnell and controversies around her.
In a series of tweets Tuesday afternoon O'Donnell reacted. "I was honored to be asked to speak at the Iowa rally this weekend and accepted. Changed my flight to make it work." In a subsequent tweet she added: "I am told things changed on their end & I will not be speaking. I truly wish them the best with this...important event."
Palin's address is drawing interest from around the nation, according to Gruschow, who said he has not been given any additional information on what the former Alaska governor may discuss at the event.
"She will make a major statement at the event," Gruschow told CNN last week. "Whether it be an announcement to run, not to run, or lay a marker in the sand for other candidates."
The rally is meant to help promote the tea party values of limited government, the importance of the Constitution and fiscal responsibility, event organizers have said.