Newlywed Britney Spears (search) got her brand-new hubby to ink an ironclad prenuptial agreement just days before they got hitched, The New York Post has learned.
The deal would protect the pop princess' $100 million fortune in case of another marital disaster.
Exact details of the legal document are not known, but it will come in handy if things go the way of Britney's first marriage, which imploded last January after just 55 hours.
Britney's decision to keep Kevin Federline (search) on a short leash when it comes to access to her vast fortune is a huge relief for her parents, who'd had heated arguments with her over the need for financial protection.
Sources inside Britney's camp said the pop tart had been unwilling to get a prenup at first — claiming she and Federline were "truly in love" and didn't need one.
But Spears' mom, Lynne, her manager, Larry Rudolph, and execs at Jive Records (search) were aghast and had spent long hours applying the screws, the sources said.
And it finally worked.
"Everything is fine. She signed a prenup. Thank God!" one source told The Post.
Another source said: "If she hadn't signed, it could have meant financial ruin for her."
In California, divorcing couples can be bound to a 50-50 split. So if Britney, 22, and Kevin, 26, were to part, it would have put half of her fortune in jeopardy.
The couple tied the knot during a five-minute ceremony Saturday night at the Studio City, Calif., home of Federline's tuxedo maker.
The nuptials were slapped together so quickly, that not even the bride's parents knew about it until the last second.
The lovebirds have not yet left for their honeymoon — taking a few days to get past their wedding hangover — but wherever they go, it will be sunny.
Spears, who has a love of the beach, told the TV show, "The Insider," she would be bringing a bikini along, adding that the wedding was, "my dream come true, a fairytale dream wedding."
Another source said the honeymoon will be in "a warm location" and "very private."
They'll need plenty of privacy if Britney is to launch her plan to start a family as soon as possible.
She told the TV show, "The Insider," she wants "to be a young mom" and earlier this year, said, "I see myself with four or five [kids]."
She's already a stepmom — Federline has two daughters by his ex-girlfriend, actress Shar Jackson (search), who had been pregnant with the second when he gave her the boot for Britney.
Whatever the future holds for Britney and Kevin, she'll probably be the one paying for it.
The singer allegedly had to buy her own $40,000 engagement ring and has put dancer Kevin on her permanent payroll as well — because he doesn't have much money of his own.
The couple will live in a Beverly Hills mansion.