Exclusive: Prince William's Bachelor Party Is Set for This Weekend!

Something tells me there might be one or two royal hangovers on Monday.

Yes, the time has finally come for Prince William's stag celebrations to commence (or, as I believe it's called in the U.S., his "bachelor party").

A royal aide tells me that this weekend will mark the start of the boys-only jolly: "It's top, top secret but the dates have been marked off in the diary and security knows every detail. For privacy reasons we can't reveal locations, but there will be plenty of booze and some legendary activities."

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Of course, expect William's brother Prince Harry to be at the centre of the shenanigans: "This is his last weekend before he starts his North Pole trek on March 29," says the source, "so he's helped out with a lot of the planning."

(Slightly less revealing was a St. James's Palace spokesman, who told UsMagazine.com: "Anything to do with stag arrangements is completely private").

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So what will Kate Middleton be up to while William, 28, is off with his friends? I hear it's business as usual for the bride-to-be, 29, who will stay in London with sister (and maid of honor) Pippa.

"Apparently there is still much to organize and sign-off," a friend informs me. "This is the first week that Kate's started to feel a little nervous. Time is ticking!"

This week we reported that parents Carole and Michael Middleton were contributing a six-figure sum to the April 29 wedding.

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Sources say this covers the wedding dress, bridesmaids' outfits and certain florist fees. But, as some of you have asked, what about the rest of the big day? Especially when security alone reportedly hits the $2 million mark.

St. James's Palace won't go into detail, but I've been reassured that the money won't be coming from the British taxpayer. "Most will come from the Queen's personal wealth, and Prince Charles will be footing much of the bill, too," explains a source.

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But there's another possible donor in the mix: the media. While print outlets, including Us, will take April 29 reporting positions on fee-free basis, I hear overseas TV companies are paying up to $190,000 to hold a camera spot at Buckingham Palace for the wedding week.

One news producer tells me: "We could only report live on location if we paid for the position. Our bill [from the Cabinet Office] came to $128,000!"

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Times that by the 300-odd expected outlets, and that could pay for a lot of cake!

By Omid Scobie, European Bureau Chief, for UsMagazine.com.

For more on the Royal Wedding, including rare photos, interviews with family and friends, details on Kate's new life as a princess and a tour of their lavish homes, order a copy of Us Weekly's Will & Kate: The Royal Wedding now.