But Gripper added that Harry and Meghan had joined New York Harry Walker Agency, which also represents the Clintons and the Obamas.
"When you've signed up to be public speakers then that kind of is their role, you are public speaking," she said.
"There's the interview that Meghan did recently - I think it was with Fortune - they pop up in this fashion, speaking over Zoom about some issue, I think it was about the internet community and that kind of thing and making the Internet a better place.
"But anyway, it's a work in progress for them."
It comes after William has just launched the environmental Earthshot Prize to help drive change and repair the planet over the next decade.
The project will reward 50 environmental pioneers for tackling problems in climate, energy, nature, oceans, pollution and fresh water.
And earlier this year, Charles launched his own Sustainable Markets Initiative, calling on businesses and communities to transition toward more sustainable practices.
It aims to bring together individuals from both private and public sectors to decarbonise the global economy.
Charles said:"Global warming, climate change and the devastating loss of biodiversity are the greatest threats humanity has ever faced, and one largely of its own creation."
He added: "Now it is time to take it to the next level. In order to secure our future and to prosper we need to evolve our economic model."
Charles also met with young climate change activist Greta Thunberg at the World Economic Forum.
