Star Mag blabs that Britney Spears has declared a no holds barred war against the mother who had her committed to rehab and snaggeda private dick to record ‘iffy’ conversations between Lynne Spears and Kevin Federline.

Brit wrote and delivered a poem to Lynne called, “Dear Momma” in which, says a source, “she told Lynne that she didn’t have a mom anymore and she couldn’t imagine a mother doing what she did to her child.”

Brit has compiled, and presented her mom with, a CD containing private conversations between Lynne and Brit’s estranged hubby Kevin Federline.

Lynne “I have to be careful that Britney doesn’t find out!” In another call, referring to the couple’s ongoing custody and financial battles, “Kevin told Lynne that he had everything under control,” adds the source. “He was just going to let Britney hang herself in court.”

Britney has cut Lynne out of her will and “is leaving all of her property and personal belongings to Jamie Lynn until her boys are of age,” says a source. “Britney is using her money to win over her sister, but Jamie loves her mom and her sister, and doesn’t know what to do!”

The Star source adds: “thinks that everyone sits at Kevin’s house and has one big laugh at her expense. She wants to put an end to this by humiliating her mother publicly. Lynne loves both Brit and Kevin, and is afraid if she doesn’t agree to Britney’s demands, she may never have a relationship with her grandsons or her daughter.”