Kate Middleton and Prince William share rare PDA moment and it's incredibly sweet

A behind-the-scenes snap of Prince William and Kate Middleton reveals a rare moment of public affection.

The black and white photo taken at the Earthshot Prize awards over the weekend shows Kate's hand resting on Will's lower back as the couple gaze into each other's eyes in a moment both touching and intimate.

The photo was one of three taken by royal photographer Chris Jackson, which the couple shared on Instagram after the eco-event.

The Cambridges seem to be following in the footsteps of Prince Harry and Meghan Markle by releasing the photos in black and white, as well as choosing to share the rare moment of affection.

William and Kate have always been conscious of the Queen's wishes that royal family members avoid public displays of affection.

But photographer Glenn Gratton told the Daily Mail that the Duchess of Sussex is changing all that by releasing royal photos in black and white.

Photo / Getty

Meghan, 40, and Harry, 37, have shared monochrome snaps on several important occasions, from their official engagement shoot to their first Christmas card.

In another sweet snap from the event, William pulls back a curtain as he and Kate are pictured laughing and smiling together.

Other photos show the pair reflecting before they head on stage to give their speeches about looking after the environment for coming generations.

Jackson, who is the husband of Kate's close friend and stylist Natasha Archer, took to Instagram to explain how he captured the series of photos from the Earthshot Prize Awards.

He wrote, "Some of you may have noticed I was a little quiet after the Earthshot awards…

"This was because I had a fantastic opportunity to shoot 'behind the scenes' with the Duke and Duchess of Cambridge and the groundbreaking environmental initiative that will do a huge amount to change the narrative over the next few years."

The prize is awarded to five winners each year by the Royal Foundation for their contributions to environmentalism.

Famous guests at the ceremony included Sir David Attenborough and Dame Emma Thompson.

Kate stunned in a re-worn Alexander McQueen dress, while William sported a polo neck and green velvet jacket.

Photo / Getty

This article was first published by the NZ Herald and is republished here with permission