Speaking to Fox News, the judges of the hit talent-spotting show added that the star, who has five studio albums to her name, would need to make some changes.
Cowell, who previously said that Spears' performance at the MTV video music awards would not be good enough to get her past 'X Factor' auditions, stated that the trio would target the star's image.
"We plan to buy her underpants, get her bigger shorts to perform in and get her away from her stupid friends," he said.
Fellow judges Randy Spears and Paula Abdul added that they would welcome the star with open arms.
Spears' performance of new single 'Gimme More' was not enough to please the audience, as media and performers alike criticised the star for being lethargic and unprepared. Reports of the singer's club-hopping and drinking before the show have also been doing the rounds.
Meanwhile US magazines report that the singer, whose latest album is due to be released in November, is reportedly in talks with producers of the Emmy awards regarding another live performance this Sunday.
