In a video message for Earthshot Prize participants, Prince William spoke of the "saddest of circumstances" that prevented him from travelling to the New York event.
The Prince of Wales was due to take part in an innovation summit today (21 September) for the environmental initiative he founded, in the run-up to its awards.
Jacinda Ardern introduced the video from the prince at the summit, where he said: "During this time of grief, I take great comfort in your continued enthusiasm ... Protecting the environment was a cause close to my grandmother’s heart."
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