Kelly - who won the first season in 2002 - and Jennifer - who placed seventh in 2004 - have been approached by producers to join the panel of the new series after they decided to replace Mariah Carey, Nicki Minajand Keith Urban.
A Fox source told E! News: ''Nothing is final yet, it's 95 per cent there. The alum panel will be Fox's attempt to reignite ratings by bringing back 'Idol' faces that the fans care about. It's 'Idol' stars guiding the next generation''
The decision to return to a three judge format for the first time in five years was reportedly made in a bid to combat the Fox show's declining ratings as it enters its 13th season.
Kevin Reilly, Fox's entertainment chairman, said: ''The format will have fresh twists for next season.''
Kevin went on to hint the expanded middle rounds were likely to be revamped since he believes they are responsible for dwindling viewing figures.