Celebrity biographer Ian Halperin has lashed out at Britney Spears' mother Lynne, insisting she selfishly pushed the singer into fame.

Halperin spent 18 months as an undercover paparazzi getting close to the pop singer and her inner circle of managers and friends, and now plans to release a book full of his findings.

In his forthcoming book Stalking Britney: Under Siege with Britney Spears, he attacks Lynne - who recently defended herself against accusations of being a pushy stage mother in her own book about her life raising Britney, entitled Through the Storm: A Real Story of Fame and Family in a Tabloid World.

Halperin says, "Lynne is a spin doctor and a borderline manic-depressive. She wants to come across as very innocent, but she only rushed to Britney's side when Britney had her emotional breakdown because there was a big rush for Britney's fortune.

"It's ridiculous that she says she didn't push both these kids into showbusiness. (The parents) thought she would be a cash cow to set them up for their future."

His book is scheduled to hit shelves in November (08). (c) WENN