Frank Oz has levelled criticism at the recent Muppets movie.
The former Muppeteer and creator of Miss Piggy and Fozzie Bear, who retired from voicing the characters a decade ago, admitted he had some reservations about the film at the Saturn Awards in Los Angeles.
"I've got to be careful here because I don't want to hurt anybody, but the Disney process bothered me," said the 68-year-old.
"I thought the film was really sweet and fun, a little too safe, a little retro. I prefer more cutting edge in the Muppets."
Frank - who was honoured with the lifetime achievement award at the ceremony celebrating science fiction, fantasy and horror - worked with Jim Henson to create famous pairings including Sesame Street's Bert and Ernie, and Kermit and Miss Piggy on the Muppets.
"The main thing is everyone finally got back to appreciating the Muppets. What I wish they appreciate are the performers underneath the Muppets - those are the key people," he said.
The British-born voice actor, who has also voiced Star Wars' Yoda, revealed that he keeps his enthusiasm and passion for the job.
"I don't do it for awards. If you start doing it other than the joy and the craft of bringing something to life and making something transcend, you're in trouble," he said.
"I remember when I did Yoda, and George [Lucas, director] tried to get me an Academy Award. It was very sweet of him, but what matters to me is, is the work good?" added Frank.