The 'Young' singer dismissed suggestions of tension emerging on the panel, saying that she had actually scolded Scherzinger for being "too nice".
"Everyone keeps asking me, 'Can you expect any brawls this year, or dramas?' But Nicole is just such a sweetie," Contostavlos told The Sun. "She's too nice. It will never happen."
"I even tell her, 'Come on Nicole, be a meanie, toughen up'. But that's just who she is.
"She's a lovely, girl-next-door, down-to-earth person who is extremely talented. And she knows her stuff."
Contostavlos recently hit back at "bulls**t" reports of a feud with Scherzinger on Twitter, telling the press to "p*ss off" and stating: "Ur always guna try and make a headline cus uve got nothin good 2 write about."
Scherzinger's emotions got the better of her during last week's X Factor Boot Camp in Liverpool when she was reduced to tears by a contestant's heartfelt performance.