Doug Wright said Wednesday Gibb is recovering in the hospital after intestinal surgery over the weekend and has been forced to cancel a number of commitments.
Gibb is slated to return to the stage on April 10 for a performance of a requiem for victims of the Titanic disaster.
The 62-year-old Gibb was hospitalized late last year for stomach and colon problems, but told the BBC last month he was making a good recovery. He did not disclose the nature of his illness but said a growth on his colon had been removed.
The Bee Gees had a string of hits in the disco era, including "Stayin' Alive."