The Princess of Wales stunned the crowd as she and her husband the Prince of Wales hosted a glitzy gala ceremony for William’s Earthshot Prize in Boston.

Kate looked thrilled to see her old friend David Beckham as she puckered up for a kiss with the football star, who made a surprise appearance at the star-studded occasion.

William also looked delighted to see Beckham, who was given a police escort to the environmental awareness event.

Kate took a break from her normally-reserved style and stole the spotlight with her rented neon green off-the-shoulder gown.

She also wore a stunning diamond-and-emerald chocker that once belonged to the late Princess Diana.

It is believed that the sparking choker is worth more than $15 million and was gifted to her late mother-in-law by the Queen, who also received it from her grandmother Queen Mary.

The former Princess of Wales wore the choker on many different occasions, also matching it with a green off-the-shoulder gown when she attended a 1993 event in London.

Kate also decided to add more sparkle to her appearance with a pair of matching Asprey diamond-emerald earrings, which she recycled from her own collection to keep the theme of the sustainable event.

She also looked very comfortable in her pair of sparkling Gianvito Rosi heels, which she has worn on several occasions in the past.

Kate wore her long hair in her signature loose waves but she decided to pull it back behind her ears to let her jewels and the off-the-shoulder gown stand out.

The Prince of Wales kept things classic with a black tuxedo, a dark navy velvet jacket and a black bow tie.

What are your thoughts on this? Let us know in the comments section and SHARE this story with your friends and family!