Sienna Miller fired from movie because she is too sexy for fat and gross Russell Crowe!

Right Said Fred said it best...."I'm too sexy......."

RUSSELL Crowe is throwing his considerable weight around the pre-production of "Nottingham," telling producers to get a new director, demanding script rewrites and, now, forcing Sienna Miller out of the flick.

Miller, who was to play Maid Marian, left the movie yesterday after being "put on hold" while shooting was pushed back from February to April.

An insider said, "It is a mess. Russell never lost the weight he put on for 'Body of Evidence' - and so the love scenes between him and Sienna would have been laughable. He's so old and fat and she's so young and gorgeous. It's just . . . gross."

Word in Hollywood is that producers are "looking for an older, plumper actress to play the role so [Crowe] doesn't look like a paunchy grandpa. Someone in her late 30s or early 40s." A rep for Miller - who's said to be "fine" and "about to sign onto two other movies" - declined to comment.

Crowe, who plays both the Sheriff of Nottingham and Robin Hood, is trying to lose the lard. One producer who said Crowe has to shed 35 pounds cracked, "We can't have Robin Hood looking more like Friar Tuck."

The Oscar-winner has demanded serious script rewrites. "Originally the movie was about a love triangle between Maid Marian, Robin Hood and the Sheriff of Nottingham," our tipster said. "It is now all about Russell's Robin Hood. Literally, 40 pages of script were redone and now are just devoted to him and his massive ego. It's amazing."

Despite studio denials, we hear Crowe is trying to get director Ridley Scott fired. Calls were made to several prominent directors over the holidays to find a replacement. "All of this was done behind Ridley's back," the insider said. "He has no idea."

A studio rep acknowledged that Miller was "released" but flatly denied "these rumors" and said, " 'Nottingham' is moving ahead with Russell Crowe and Ridley Scott."