Kelly Osbourne has admitted that does not regret calling Christina Aguilera "fat" last year.
The E! "Fashion Police" co-host criticized Aguilera's weight gain despite also suffering weight problems herself.
"She called me fat for years," explained Osbourne speaking to Glamour magazine recently.
The 27-year-old dropped 50 pounds last year, but still fired back at Aguilera.
"I said, '[expletive] you, now you're fat too! Now you know how it feels," said Osbourne. "I'm sorry, but I stand by that."
The daughter of famous rocker Ozzy Osbourne added that she chooses her comments on "Fashion Police" very carefully.
"I make a point on the show never to say anything about anybody that I wouldn't say directly to their face," said Osbourne. "I'm famous and she's famous. It doesn't mean I can't stand up for myself. I took it for 10 years, and finally decided to be like, 'You know what? I'm done.'"
Osbourne also divulged that she still struggles with her own personal image.
"I didn't say I wasn't fat," she explained. "You will always see in yourself what people used to bully you for… Everyone called me Kelly Smelly with the big Belly Whose Dad's on the Telly. It hurt so badly to be judged like that."
The television personality added, "Even now, I don't consider myself skinny."
Responding to Osbourne's comments in the past, Aguilera fought back against the criticism, saying she was comfortable in her own skin while promoting her television series "The Voice" last year.
"As long as I am happy in my own skin, that is all the confirmation I need," said "The Voice" coach.
A single mother after her divorce, the 31-year-old added that the entertainment business is especially difficult for females.
"Women, we are definitely under a microscope and under massive scrutiny. You got to be a strong, powerful, very confident woman," said Aguilera.