American Idol is one of Fox's success stories

Fox - who this week announced they were setting up a dedicated reality show channel - called the claims "baseless".

Last week, broadcasters NBC and ABC accused Fox of stealing ideas for reality TV shows.

But Gail Berman, Fox's president of entertainment, called accusations "outrageous" adding they were not doing anything different from their rivals.

This is the way television works. There's nothing new about this Gail Berman, Fox

In a presentation to television critics at their annual summer meeting, Berman said: "Just like scripted programming, the unscripted world has reached a point where multiple projects with similar themes are being pitched simultaneously.

"There is no need to defend ourselves. The baseless allegations of theft and extortion are outrageous and unacceptable."

Jeff Zucker, head of NBC Universal Television Group, said Fox had gone from being an innovator to being an imitator after the company unveiled a new boxing reality series soon after NBC had revealed plans for a similar show, starring Sugar Ray Leonard.

Competition

ABC Primetime President Stephen McPherson also warned creative executives that Fox would steal their ideas.

But Berman said: "I think it's important that you know there were five other boxing shows pitched around town after they pitched their show."

She added that they tried to buy what became NBC's The Contender before settling on their series.

"This is the way television works. There's nothing new about this. This is a competitive business," Berman said.