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Mel Gibson has had a major falling out with "Flashdance" and "Basic Instinct" screenwriter Joe Eszterhas, with whom he had been collaborating on a film about a Jewish warrior titled "The Maccabees."

In a letter written by Eszterhas to Gibson and obtained by TheWrap.com, Eszterhas makes several explosive accusations, which Gibson calls "utter fabrications."

Among them: Gibson used slurs to refer to Jewish people; he referred to the Holocaust as "mostly a lot of horses***"; he threatened to kill the mother of his young daughter, Oksana Grigorieva; and he said he's glad John Lennon is dead and that the former Beatle "deserved" to be shot.

Eszterhas alleges that Gibson participated in the project "in an attempt to deflect continuing charges of anti-Semitism which have dogged you, charges which have crippled your career." Gibson famously made anti-Semitic remarks during a DUI arrest in Malibu, California, several years ago.

Eszterhas further claims, "I've come to the conclusion that the reason you won't make 'The Maccabees' is the ugliest possible one. You hate Jews." The letter states that Gibson admitted he was involved in the project so he could convert Jewish people to Christianity.

The Los Angeles Times reported Wednesday that Warner Bros. put the project on hold after rejecting Eszterhas' script.

Gibson strongly denied Eszterhas' claims in a separate letter published by Deadline.com. Gibson writes that Eszterhas failed to write a script or an outline in a timely fashion, and as a result Gibson reacted "more strongly than I should have."

He says he subsequently sent Eszterhas a written apology, "the colorful words of which you apparently now find offensive. Let me now clearly apologize to you and your family in the simplest of terms."

Gibson writes that Eszterhas' script was rejected because it was "substandard" and a "significant waste of time," and not because of any other factor.

Gibson concludes his letter by writing, "I think that we can agree that this should be our last communication."

The Oscar-winning actor/director also stated in his letter that he planned to continue developing the project, which he started more than 10 years ago. "I absolutely want to make this movie; it's just that neither Warner Brothers nor I want to make this movie based on your script," he writes to Eszterhas.

"The Maccabees" is based on the life of Judah Maccabee, who led a Jewish revolt against the Greek-Syrian armies in the second century B.C.