Kate Middleton's photographer said she was 'fearful' before her birthday shoot because she wasn't used to posing

• Kate Middleton was photographed by Paolo Roversi for her 40th birthday.
• Roversi told the Italian newspaper Corriere della Sera that she was nervous for the shoot.

The Duchess of Cambridge's photographer Paolo Roversi has opened up about what it was like to shoot the royal for her 40th birthday portraits.

On Sunday, the Italian photographer released three new photos of the royal in London's Kew Gardens, in which she posed in Alexander McQueen gowns.

Speaking to the Italian newspaper Corriere della Sera, Roversi said he met Kate Middleton for tea at Kensington Palace ahead of the shoot in November, which she had been nervous about.

"But at first the Duchess was apprehensive. Every day she is machine-gunned by photographers but not used to posing," Roversi told the newspaper, according to Hello! Magazine.

"Knowing my photos with the models she was a bit fearful in facing a real session, which then required about four hours of work. But once she started it would be very easy, I reassured her," he added.

The photographer said that he ended up taking 250 photos of the duchess, and that he asked her to dance for him during the shoot.

"In the end I wanted to take pictures in motion, so with that wonderful wide skirt I made her dance in front of my lens, a kind of accelerated waltz mixed with a pinch of rock 'n roll," he said, according to Hello! Magazine.

Royal experts believe that the photos were inspired by photos of historic monarchs, such as Queen Victoria and Queen Elizabeth. "The photographer has clearly been inspired by Cecil Beaton's portraits of the Queen and the Queen Mother," the royal commentator Richard Fitzwilliams previously told Insider.

"Catherine's interest in photography and her patronage of the National Portrait Gallery were highly significant in choosing these poses. Above all, these photographs are those of a future queen," he added.

Paolo Roversi did not immediately respond to Insider's request for comment.