The former nurse, who married the King of Pop in 1996 and filed for divorce three years later, made her first public appearance at her California ranch since the star's death at his Los Angeles home on June 25.
Her decision to appear in public was suggested as the first stage of a bitter PR battle with the Jackson family over the custody of Prince Michael I, 12, Paris, 11, and for seven-year-old Blanket, who is not her child.
"They are my flesh and blood. I am going after my children," the Daily Star quoted her as saying from the doors of her bungalow.
The 50 year-old said that she was ready to undergo a DNA test to prove her biological claim to the older Jackson kids, and that the singer was not their father.
She said: "Michael was divorced, lonely and wanted children. I was the one who said to him: 'I will have your babies.' I offered him my womb - it was a gift. It was something I did to keep him happy. I was just the vessel. It wasn't Michael's sperm. I got paid for it, and I've moved on."
Debbie recently won a postponement of a court custody hearing scheduled for July 6.