The Duke and Duchess of Cambridge stepped out on Sunday to attend the Earthshot Awards.

Guests for the event were told not to purchase new clothing for the event, but instead wear something they already own.

Prince William apparently dug through his closet and emerged with a sleek green velvet tuxedo, which he wore sans-tie over a turtleneck for the event, at which he and his wife were the guests of honour.

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Kate Middleton likewise recycled her outfit, a pale lilac-coloured gown, which the Daily Mail noted she’d first worn to the 2011 BAFTA ceremony in Los Angeles.

AP Photo/Scott Garfitt
AP Photo/Scott Garfitt

Check out photos of some of the other celebs in attendance at the 2021 Earthshot Awards, including Emma Watson, Emma Thompson, and David Oyelowo and wife Jessica.

AP Photo/Alberto Pezzali, pool
AP Photo/Alberto Pezzali, pool
AP Photo/Scott Garfitt
AP Photo/Scott Garfitt
AP Photo/Scott Garfitt
AP Photo/Scott Garfitt

Five winners each receive a $1.3-million prize to advance their work in five individual categories: Protect and Restore Nature, Clean Our Air, Revive Our Oceans, Build a Waste-Free World, and Fix Our Climate.