Louis Walsh criticized last year's 'X Factor' judges Rita Ora, Nick Grimshaw

Louis Walsh, who is returning as the X Factor judge this season, dissed Rita Ora and Nick Grimshaw, branding the pair 'inexperienced,' 'lightweights.'

The 63-year-old star, who is getting back along with Sharon Osbourne and Nicole Scherzinger, insisted that he would only go back if there was a panel "who knew what they were talking about," reports the Mirror.

"Sharon and I are old, but that means we're far more experienced, unlike the young whippersnappers on last year's panel who didn't know a thing about talent. Sharon and I pushed for Nicole, we didn't want Rita Ora. It turned into a fashion show. The panel didn't have the right credentials. They were lightweight," he added.

Chatting to Best magazine about his return, Walsh further said, "I'm back with a vengeance."

His comments came after boss Simon Cowell admitted that hiring Ora and Grimshaw was a blunder.

"When we announced the new line-up, it was 95 percent positive. No one was saying it was a mistake and that was what we were getting last year," he said.

The new series of 'X Factor' will be returning on TV screens this month.