'American property tycoon Donald Trump has a message for newly-engaged singer Britney Spears - "get a prenuptial agreement" before she weds dancer Kevin Federline. The Apprentice reality TV star lost GBP13.8 million to first wife Ivana in 1990 and made sure he signed a prenup with second wife Marla Maples. The stunning model walked away after seven years of marriage with a GBP1.1 million payoff. Trump proposed to Slovenian beauty Melinia Knauss in April (04), while Spears agreed to marry her boyfriend of three months in June (04) after a whirlwind romance. In an interview with American TV show Entertainment Tonight, Trump says, "I heard Britney Spears is not going to have a prenuptial agreement. She's making a huge mistake. Just a huge, traumatic and potentially ruinous mistake. "You have to have it. You're just doing yourself a tremendous disservice if you don't have a prenuptial agreement. "It's a horrible instrument. It's a horrible thing to be talking to your future bride or husband for the next 100 years and you say, 'Darling, when we get divorced, this is what is going to be. It's all horrible. But if you don't have it, it's just a tremendous mistake.'