(NEW YORK) -- Donald Trump can cross another celebrity off his holiday card list.
Trump is firing back at David Letterman after the Late Show host said on the air that the Apprentice star's pursuit of President Obama's birth certificate has started to "smack of racism."
According to The New York Post, Trump canceled an upcoming appearance on Letterman's show with a letter that read, "I was disappointed to hear the statements...that I was a 'racist.' In actuality, nothing could be further from the truth and there is nobody who is less of a racist than Donald Trump. Based upon your statements, and despite the fact that we have always done so well together, especially in your ratings, I am canceling my May 18 appearance on your show."
The real estate mogul and potential presidential candidate continued, "Please inform your staff that I will likewise not do the 'Top Ten' list that they had been trying to set up."
Trump, whose recent questioning of Obama's birthplace and college grades has earned him criticism from celebrities like Robert De Niro and Jerry Seinfeld, said he'd only appear on The Late Show again if Dave is "ready to apologize."
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