Pirates of the Caribbean 4 In Trouble

Johnny Depp has hinted that the Pirates of the Caribbean 4 project could be in trouble.

The popular actor appeared with good friend and Disney's chairman Dick Cook to announce that a fourth Pirates movie was going ahead earlier this month.

Since then Cook has been fired from the company. Depp revealed that he agreed to reprise the role of Jack Sparrow because of his friendship with Cook.

In an interview with the Los Angeles Times the actor said: "There's a fissure, a crack in my enthusiasm at the moment... It was all born in that office,"

" He said, 'We're thinking about doing this Pirates Of The Caribbean movie', I said I was in. This was before there was a script or anything."

Pirates of the Caribbean and Jack Sparrow is Johnny Depp's most famous role and saw him land a Best Actor Oscar nomination for Curse of the Black Pearl back in 2003.

Two movies followed, with Dead Man's Chest breaking the $1 billion barrier. Despite rounding up the trilogy of movies in 2007 it was left open to a possible fourth movie.

Entitled Pirates of the Caribbean: On Stranger Tides and will see Jack Sparrow once again team up with Barbossa to search for the Fountain of Youth.

The film is expected to be released in 2011.