The new figures were dressed in replicas of the outfits they wore when announcing their engagement in 2010.

Their engagement and wedding in April last year have triggered a resurgence in the popularity of the British monarchy, which is expected to build this summer when the country celebrates Queen Elizabeth's 60 years on the throne.

The Duchess, then Kate Middleton, appeared at the engagement announcement in a blue Issa dress and a sapphire and diamond ring once worn by Diana, Princess of Wales, William's late mother.

The ring has also been reproduced, although it was obscured by a handbag at Madame Tussauds, where dozens of photographers and camera crews showed up to capture the models.

Madame Tussauds in New York and Amsterdam were to reveal their own versions of the models on Wednesday wearing different outfits.

In New York, the duchess is dressed in a replica Alexander McQueen floor-length gown and Amsterdam will show her in a version of the lace Alice Temperley number she wore at the red carpet premiere of "War Horse".

According to the waxwork attraction, its relationship with the British royal family goes back to William IV who was king when the first attraction opened in London in 1835.

Queen Elizabeth has sat six times for the studio team working on her models.

The Duke and Duchess of Cambridge did not personally attend a sitting for their beaming reproductions, but were "closely involved and kept informed at every stage of the process," Madame Tussauds said.

Each figure cost around 150,000 pounds to create and took a team of sculptors and hair and colour artists four months to complete.

(Reporting by Mike Collett-White, editing by Paul Casciato)

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