United Kingdom, July 22 -- A new portrait of Prince George has been released to mark his 13th birthday.

The young prince - who is the oldest child of Prince William and Catherine, Princess of Wales - posed in a dark suit, with his white shirt unbuttoned at the collar and without a tie, in the image, which was taken by photographer Matt Porteous at Kensington Palace after Trooping the Colour last month.

The image was shared on William and Catherine's social media channels along with a caption that featured a party popper emoji and the words: "Happy 13th birthday, George!"

This is set to be a big year for George, who is second in line to the throne, because he will be starting a new school in September.

It was recently confirmed the pri...