The Prince of Wales said he was "deeply worried" about the planet he would leave behind for Princes William and Harry as he spoke of the "depressing trajectory" of wildlife loss on Earth.

Introducing a WWF lecture at the Royal Society, the Prince said he was alarmed to realise that the world was on the brink of a sixth mass extinction and was entering a new geological age because of the actions of humans.

The Prince of Wales, who is president of WWF-UK said: "As a father and grandfather I worry deeply about the world we are leaving behind for our successors. We are rapidly destroying our means of survival.

"Clearly we are not living within the environmental limits of our plants. Populations of vertebrate species have declined by more than half from 1970. We are on a deeply depressing trajectory to witness the sixth global mass extinction in our planet.

"We are ushering in a new era. It's alarming to realise that after 4.5 billion years that a change in epoch has been due to the activities of just a single species."