"I made a mistake," he told Oprah Winfrey during Thursday's show. "I made a lot of mistakes in writing the book and promoting the book."

Did you lie or did you make a mistake? "I think probably both," he said.

Winfrey, whose endorsement of A Million Little Pieces turned into it into one of the top-selling books of 2005, retracted her support of the author, saying she felt "conned" by him. "It's embarrassing and disappointing for me," the talk-show queen said.

And even while Frey admitted altering information that he presented as facts, he maintained his book is a memoir.

"I don't think it's a novel. I still think it's a memoir," he said. "I don't feel like I conned you. I still think the book is about drug addiction and alcoholism and no one is disputing that I was a drug addict and an alcoholic, and it's about the battle to overcome that."

Among the facts he admitted to embellishing: he was jailed for only a few hours, not 87 days; and each character in the book wasn't wholly represented.

Winfrey also apologised to viewers for calling CNN's Larry King two weeks ago and lending her support to Frey.