Buckingham Palace shares kids heartfelt appeal to King Charles

King Charles III, who's battling cancer, has received touching messages from brilliant children as the royal family marked World Earth Day on Monday.

The royal family's social media accounts shared touching letters from the children, asking King Charles to save their future, with one smart child writing: "I'm worried about climate change and global warming."

The Palace shared the letters with the caption: "Each year, The King receives thousands of letters from children and young people who want to get involved in saving our planet.

"We’d love to hear about what you and your families, friends, colleagues and communities are doing to help combat the damage which plastics are doing to the environment - please tell us more in the comments."

Earlier on the day the  palace shared a meaningful video with a warning from King Charles.

The video was captioned: "Planet vs. Plastics."

"On 19th February 1970, at the age of 21, The King warned of the dangerous effects of plastic pollution on the environment. In the five decades since, His Majesty has used his unique position to champion action for a sustainable future."

It comes as the royal family marked World Earth Day while celebrating the achievements of the environmental movement.