Organizers of the annual Bud Billiken Parade on Chicago's South Side insisted Wednesday that President Barack Obama had been confirmed as the grand marshal for the annual event, but on Thursday a campaign official said Obama's schedule couldn't accomodate the visit.

Parade Chairman Col. Eugene Scott told the Chicago Tribune he was wary that the news came from Obama's campaign team since his previous communication had been with the White House exclusively.

On Wednesday, Scott told WBEZ he was "100 percent sure" that the President would lead the parade, and that his appearance had been kept under wraps while federal and city officials map a security plan.

Obama would have been the first sitting president to attend the August 11 event, which typically draws more than a million spectators, according to ABC Chicago. Prior to his presidency, Obama had been a fixture at the parade, serving as grand marshal four times as a senator and presidential candidate.

The back-to-school event is one of the oldest and largest African-American parades in the country. Organizers previously announced that, in honor of Obama's appearance, this year's theme was to be "Education: Built to Last, a Tribute to President Barack Obama," according to WGN.

The Bud Billiken parade has been held the second Saturday in August since 1929, and celebrates Chicago's youth, according to the parade website. This year's celebration will be the 83rd installment of the event, which kicks off in Bronzeville near 39th Street and South Martin Luther King Drive and marches to 55th Street at Washington Park.