Donald Trump fired himself on Thursday as the celebrity pace-car driver for the Indianapolis 500, calling it "inappropriate" since he may be announcing his intention to run for president of the United States.

"We had conversations with him that started yesterday, and he was talking about his concern that he may make an announcement for president ahead of the race, and that it may be inappropriate to drive the pace car," track spokesman Doug Boles told the Associated Press. "So we discussed the political ramifications for everyone, we spoke with him again this morning and he decided to pull aside." Trump also said it would be impossible to fulfill the required practice sessions that occur late in race week because of his busy schedule.

There had been considerable opposition to Trump driving the pace car, with a "Dump The Donald" movement growing.

Race organizers had selected the real estate mogul as this year's celebrity pace car driver a month ago but since then, the potential Republican presidential candidate has created a stir by questioning whether President Barack Obama was born outside the U.S.

Race fans, local citizens and an Indiana state lawmaker wanted Trump out of the May 29 race — the 100th anniversary of the annual race at Indianapolis Motor Speedway.

"To me, when they first named Donald Trump, it just felt wrong," said Michael Wallack, who started a Facebook page in hopes of firing Trump. "He has no relationship to the track, to the race, to racing, to Indianapolis, and I think I would have been bothered anytime with something like that. But to do that on the 100th anniversary, it made no sense."

A replacement is expected to be named later this month.