Kate Middleton dazzles in Alexander McQueen dress at Diamond Jubilee pageant

Kate Middleton wore a stunning scarlet Alexander McQueen dress to join the Queen and Prince William for the Diamond Jubilee pageant

It may have been the Queen's Diamond Jubilee, but Kate Middleton stole the style show as she attended the monarch's celebratory River Thames pageant yesterday, in a stunning scarlet Alexander McQueen dress.

KATE MIDDLETON: YEAR IN STYLE

Braving the wind and drizzling rain, the Duchess of Cambridge banished grey skies with her eye-catching ensemble, a vibrant red, long sleeved dress with a pretty, pleated skirt, by one of her design favourites, Sarah Burton for Alexander McQueen.

The dress, from the label's Pre-Fall 2011 collection, comes with an eye-watering £1,195 pricetag, but had reportedly sold out online by the end of the day.

Kate topped her patriotic ensemble off with a matching Lock and Co. hat (VERY firmly secured in place!), her favourite nude L.K. Bennett heels, delicate Kiki McDonough citrine drop earrings and a matching red clutch.

Always one for practical fashion, the Duchess also took a tartan scarf along for the day, in case it got too breezy as the royal party traveled along the Thames.

Stunning Kate Middleton's dress certainly was, but we couldn't help feeling we'd seen it somewhere before.

And that's because we have.

Reality TV Queen Kim Kardashian and X Factor starlet Tulisa Contosavlos have both worn the scene-stealing Alexander McQueen number in the past.

But who wore it best?

You decide!

What are your thoughts on Kate Middleton's sizzling scarlet dress? Love or hate? Let us know in the the comments box below...

WHO WORE IT BEST? KATE MIDDLETON VS. KIM KARDASHIAN VS. TULISA

KATE MIDDLETON: YEAR IN STYLE

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