Fashion guru Trinny shows...what not to bare at Elton's White Tie and Tiara party

The plunging back line of the outfit served only to accentuate the backbone of the famously skinny television presenter.

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Don't look back: A very thin Trinny Woodall arrived at Sir Elton John's party in an emerald green gown which plunged to reveal her backbone

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Trinny was a guest at Sir Elton's annual White Tie and Tiara party

The 42-year-old's bony arms were also made to look even thinner by the heavyweight bracelets she wore.

Miss Woodall is pictured arriving at Sir Elton's Windsor home for his White Tie and Tiara party.

Another guest was her TV co-presenter, the somewhat more voluptuous Susanna Constantine.

Las Vegas came to Berkshire as the singer underlined his reputation for extravagance by filling his house with showgirls dripping in diamonds, dozens of Elvis lookalikes, slot machines and roulette tables, and even an ice sculpture replica of the Vegas Strip.

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Las Vegas came to Berkshire at Elton's John's glamorous White Tie and Tiara Ball

Among the 600 guests, who paid £1,000 a ticket, were Kate Moss, Elizabeth Hurley, Elle Macpherson, Hugh Grant, Gordon Ramsay, and Fergie. Sir Elton sang, as did Sir Tom Jones.

TV chef Gordon Ramsay hurriedly put the finishing touches to his outfit as he arrived with wife Tana at Elton John's Old Windsor home. At least Ramsay was wearing the right-coloured tie - Michael Caine arrived at the charity event in black shirt and tie.

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Gordon Ramsay makes a quick adjustment as he arrives with wife Tana

Sarah Ferguson arrives with her usual party companion daughter Beatrice

Other guests, including Princess Beatrice and her mother Sarah Ferguson, Dame Shirley Bassey and Tom Jones, were greeted by Elvis Presley lookalikes.

The Duchess of York wore her low-cut white dress with a Marquise diamond choker with matching earrings. Princess Beatrice also wore jewellery by Chopard, the jewellery company which helped to organise the party.

As guests arrived they made their way past the original stage inflatables from Elton John's Red Piano Las Vegas Show.

They were then led down a hot-pink carpet, and past ice sculptures carved into the shape of famous Las Vegas hotels and draped with diamond jewellery.

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Dame Shirley Bassey arrived to party having recovered from her recent helicopter scare

David Walliams arrives with favourite companion Lisa Snowdon

One offer at the fund-raising auction was a day of tennis coaching by Roger Federer, as well as the latest Audi A8 and the most exclusive convertible Rolls Royce Drophead Coupé. All proceeds from the evening will go towards the Elton John AIDS Foundation.

After the auction, the entertainment was provided by Dame Shirley Bassey, Tom Jones and the party host himself.

Last year, the White Tie And Tiara ball cost £1,000 a head and raised £4.6 million for charity.

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Party planners: Elton with partner David Furnish who helped plan the A-list bash

Jimmy Choo owner Tamara Mellon wears a Grecian style white gown

Still stunning Shakira Caine, the wife of actor Michael

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But the pace was too hot for some - Elle Macpherson was spotted sloping off at around 2.30am, just after her former partner Arpad Busson made his exit.

Graham Norton and companion arrive in matching suits

Simon Cowell's girlfriend Terri Seymour, right, arrives with a friend