Prince Charles opened the Think 07 conference on sustainable development this morning by declaring: 'This is an emergency.'

Speaking via a live video link-up in his capacity as president of Business In the Community, the prince urged his audience to reduce the carbon emissions for which they are directly responsible, and also to work with suppliers and customers to help them cut their carbon emissions.

He said: 'I am delighted to hear that the property and construction sectors are gathering today to discuss their response.'

He also called for developers and designers to adopt environmentally friendly materials and to work towards the world inhabiting sustainable communities.

The prince acknowledged that many businesses were 'still sceptical' but warned that uncontrolled climate change will lead to 'an unstable world' that damages the entire global economy, as millions suffer flooding and crop failure.

'If the scientific concensus about climate change is right, and there is no doubt that it is, doing nothing is not an option,' he added.

Up to 4,000 people are expected to attend the three-day Think 07 conference and exhibition at London's Excel centre.

For more details, go to www.think07.co.uk/registration