Our planet is just five years away from climate change catastrophe - but can still be saved, according to a new report.

The World Wide Fund for Nature (WWF) warns governments have until 2012 to "plant the seeds of change" and make positive moves to limit carbon emissions.

If they fail to do so, the WWF's Vision For 2050 warns "generations to come will have to live with the compromises and hardships caused by their inability to act".

"We have a small window of time in which we can plant the seeds of change, and that is the next five years," James Leape, from the WWF, said.

"We cannot afford to waste them. This is not something that governments can put off until the future."

Between now and 2050, the world's energy needs are expected to double.

But the Climate Solutions document says technologies already available could be harnessed to produce enough sustainable energy to power the planet while also reducing greenhouse gas emissions by 60-80%.

The WWF report also states that nuclear power is not necessary to cut carbon emissions.

The finding is in stark contrast to the UK Government's insistence upon the need to go nuclear.

Keith Allott, head of WWF-UK's climate change programmes, said: "This report shows that although the scale of the climate change challenge can seem daunting, it can be tackled provided we act with real urgency.

"We can slash carbon emissions and meet global energy demand without resorting to the red herring of nuclear power.

"The big question is whether the world's statesmen will have the strength and vision to make this happen - and Britain will be key to that."