"We are consuming the resources of our planet at such a rate that we are, in effect, living off credit and living on borrowed time," the future king has warned.

Charles, once mocked for admitting he talked to the plants in his country garden to make them grow, has long been an impassioned environmentalist, promoting organic farming and a sustainable approach to agriculture.

Now he has taken up the green crusade on the home front.

Wherever possible, he is to cut down on private helicopters and chartered planes and rely more on scheduled flights and trains. His official Jaguar cars which are being switched to 100 percent biodiesel fuel.

Staff at his Clarence House residence in London have been given two bicycles for pedalling around the British capital to meetings. In London gridlock, that often makes practical as much as environmental sense.

"We will be trying to cut down on our carbon emissions in everything from travel to how he runs his own household," a spokesman for the prince told Reuters on Friday.

"We will be turning lights off whenever possible and turning computers off when they are not needed. He and his staff are determined to reduce the impact on the environment and do what they can to tackle this hugely important problem," he added.

Charles and his wife Camilla might even cut back on holidays abroad and vacation closer to home.

"The Prince knows like anyone else that it is all about individual as well as collective responsibility," the spokesman added.

Rebelling against what he has called the "soulless, mass-produced food that had come to dominate the modern diet," Charles has also campaigned to reconnect farmers and consumers.