Justin Bieber's maternal grandparents Bruce and Diane Dale were snapped on the red carpet with him and mom Pattie Mallette at last week's premiere of his upcoming film 'Believe,' out on Christmas Day. Noticeably absent from the festivities were his paternal grandparents, George and Kathy Bieber. What's up with that omission?

Word is the Biebs banned them from coming. Or, at the very least, he didn't extend an invitation.

George Bieber, who resides in Ontario, Canada, said he and his wife would have loved an invite to the premiere to share in Biebs' joy ... but they were not asked to come. Gramps Biebs was asked about his relationship with Justin, which appears to be strained. "I really don’t want to talk about it," he said.

George had spoken out about their estrangement earlier this year, saying that the famous teen "never calls us, and now I sometimes think he doesn’t care. It does make me sad, as right now our lives are pretty desperate." He doesn't work due to illness, while his wife works manual labor for 40 hours a week despite a bad back.

Gramps said that his grandson "has just got too big for his britches." But despite their fractured relationship, he remains proud of his offspring, saying, "He will always be my grandson, and I am and always will be so proud of him. It’s just sad that he is not a bigger part of our life."

It's Christmas – time to mend fences? Extend an olive branch?