Tony Blair last night attempted to use a keynote speech on climate change to persuade the Bush administration of the growing need to tackle environmental pollution.

The prime minister praised the "consistent evolution" of American policy under President Bush at the World Economic Forum in Davos.

He also supported the American stance that extra financial help for development in Africa depends on good governance.

However, he said that it was vital for G8 countries to be united, claiming a fragmented approach would result in rivalry and conflict.

The French president, Jacques Chirac, used his speech - which was made via satellite link - to propose international taxes on greenhouse emissions.

Meanwhile, Britain is ranked 66th out of 146 nations in the latest Environmental Sustainability Index out tomorrow.