I firmly believe we are only three years away from a tipping point. By 2010, the world will need to have agreed once and for all upon how it wants to tackle climate change.

It is only since the early part of 2006 that companies have started to focus on the issue of sustainability with greater urgency. A year since I pledged $3bn of Virgin Group profits towards developing the cleaner fuel technology of the future, we have made great progress. The aviation industry is also working harder to find solutions, through its Sustainable Aviation Strategy for example. But now it is for governments to do more to achieve international momentum.