Prince William and Sir David Attenborough warn that humans 'need to be careful'

The Duke of Cambridge and the naturalist spoke of the 'need to be careful' with our natural environment at the World Economic Forum in Switzerland.

The Duke of Cambridge spoke to the 92-year-old broadcaster and naturalist on their shared passions for conservation, tackling climate change and Sir David's long broadcasting career.

The 'Blue Planet' narrator was questioned on advice he would give to people of those born of the Duke's generations.

He replied: "We have to recognise that every breath of air we take, every mouthful of food that we take comes from the natural world, and that if we damage the natural world we damage ourselves.

"We are one coherent eco-system, it's not just a question of beauty or interest or wonder, it's the essential ingredient, the essential part of human life is a healthy planet."

He also spoke on plastic pollution calling it "appalling damage on marine life - the extent of which we don't yet fully know."