Director Todd Phillips said in a statement: "I thought Mel would have been great in the movie and I had the full backing of Jeff Robinov and his team. But I realize filmmaking is a collaborative effort, and this decision ultimately did not have the full support of my entire cast and crew.”
Gibson was expected to make a cameo in Warner Bros.' sequel but actor Zach Galifianakis and others involved in the project were reportedly furious with the idea.
In a podcast interview with Comedy Death Ray earlier this month, Galifianakis said, "I'm in a deep protest right now with a movie I'm working on, up in arms about something. But I can't get the guys to [listen] ... I'm not making any leeway."
Gibson made headlines earlier this year when he allegedly made racial and threatening remarks to his ex-girlfriend, Oksana Grigorieva, which were subsequently leaked to the Web.
"The Hangover 2," which stars Galifianakis, Bradley Cooper and Ed Helms, opens Summer 2011.
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