LOS ANGELES (Reuters) - Fox TV executives threw the "American Idol" guessing game over a new panel of judges wide open on Monday, refusing to confirm or deny reports that singers Jennifer Lopez or Steven Tyler would join the top-rated show for its upcoming 10th season.
Fox entertainment chairman Peter Rice told TV journalists there were no signed deals in place with anyone "on either side of the camera".
He also refused to speculate on reports that songwriter Kara DioGuardi had been fired as a judge, or that executive producer Nigel Lythgoe was returning to "Idol" to carry out a wholesale make-over after four years of declining ratings.
"There are no signed deals with anybody," Rice said. "I can tell you that much of the information (in the media) is accurate and some of it is wildly inaccurate. I am not going to confirm or deny which ones they are," he added.
Rice said he expected a panel to be in place by the time auditions start in front of the judges in mid-September.
Speculation about the new line-up reached fever pitch last week after the shock announcement that Ellen DeGeneres would not be returning after just one year of her five year contract.
That left "Idol" producers with two spots to fill after the exit in May of acerbic British judge Simon Cowell, and fueled talk that a wider overhaul of the TV search for a new pop star was underway.
Other names of potential judges have included singers Jessica Simpson, Justin Timberlake and Sir Elton John.
"American Idol", which generates big advertising revenues for Fox and has quashed the competition on rival TV networks, remained the most-watched show on U.S. television last season.
But the contest has lost about six million regular viewers since 2006 and saw challenges to its No.1 spot this year from ABC's "Dancing With the Stars" and NBC's broadcasts of the Vancouver Winter Olympics.
Rice did hint that bigger changes were being considered for the 10th season, which will be broadcast in January 2011.
"We have to evolve without looking at what we have done in the past...Simon's departure meant there was a natural evolution and we have to look at the show and say 'how do we make a great TV show?' and continue it because we would love to be celebrating its 20th anniversary in 10 more years," he said, without elaborating.
"Idol" producers have already lowered the minimum age for contestants to 15 years-old next season, in what was seen as a bid to reconnect with younger viewers. The results show will also be cut by half to 30 minutes.
Cowell left to launch his own "X-Factor" talent show on Fox in the fall of 2011. Rice said the two shows would run at different times of year. "They are not going head to head at all, and we are excited to have both of them on our network," he said.
"American Idol" is produced by 19 Entertainment, a unit of CKX Inc, and by London-based FremantleMedia, a unit of Bertelsmann AG-controlled broadcaster RTL Group. Fox is a unit of News Corp.
Additional reporting by Dean Goodman; Editing by Bob Tourtellotte