Kate Middleton and Prince William Show Rare PDA Moment at Formal Event

The Duke and Duchess of Cambridge shared a sweet moment at the inaugural Earthshot Prize Awards.

Prince William and Kate Middleton are displaying some PDA! In a new photo from Sunday's inaugural Earthshot Prize Awards, the Duke and Duchess of Cambridge shared a sweet moment together.

In the black-and-white pic showing the rare PDA moment between the pair, Kate sweetly rests her hand on her husband's back as he leans down to talk to her.

Another pic from the event shows William looking back at a smiling Kate as they walk through a curtain. The final new shot is a solo one of the duke looking studious as he stands backstage.

"Behind the scenes at the first ever @EarthshotPrize Awards," the couple's Instagram page captioned the pics.

The royals both sported recycled formal wear to the event, which celebrated green activism.

The duke opted for a green velvet blazer, which he paired with a black turtleneck and black trousers, while his wife stunned in a lilac Alexander McQueen gown with a beaded belt. Kate previously wore the gown to the 2011 BAFTA Brits to Watch event in Los Angeles.

William launched the Earthshot Prize earlier this year, under the leadership of the Royal Foundation, as part of his and Kate's ongoing environmental advocacy efforts. Each recipient was awarded £1 million to fund their innovative solutions for repairing the planet.

Watch the video below for more on William and Kate.