"If you are looking at a global venue for your business, then there is no challenge in the global category that is anywhere nearly as important and will be as important to people as the sustainability challenge," he said in a speech at the Global Brand Forum.

China’s contribution

On Wednesday, Gore said China can cut its carbon emissions without jeopardising economic growth if it uses new technologies that do not emit greenhouse gases.

He cited the mobile phone industry as an example of a business that does not need to burn fossil fuels such as oil and coal. 

He said: "There are ways to leap-frog the old, dirty technologies.”

However, the Chinese government is worried that plans to cut carbon emissions would cripple its economic development.

But Gore has said that the Chinese government needs to be more aggressive in fighting global warming because the country's chronic water shortage is tied to climate change.

"China has a great deal at risk," Gore said.

"The water crisis is very closely related to the climate crisis."

Millions of people in China, which is on course to overtake the US as the world's biggest emitter of greenhouse gases, have no access to clean drinking water.

Chinese scientists had said last month that rising temperatures are drying up the wetlands in the Yangtze and Yellow rivers, China's two longest rivers, choking their flow and reducing water supplies to hundreds of millions of people.

While Chinese leaders have "expressed themselves forcefully" on global warming, the comments do not "necessarily lead to immediate changes in the region," Gore has said.

Slow progress

Gore, who became a "climate crusader" after he left the White House, has also urged governments to impose carbon taxes because that would force businesses to think more carefully about their greenshouse gas emissions.

"The single, most effective thing that governments can do to solve this crisis" is to have a CO2 tax, he said.

Gore said that he was embarrassed that as vice president, he had only managed to persuade one senator to vote for the Kyoto Treaty.

While he feels that the majority of them would vote for it today, he stressed the need for people to have a greater "sense of urgency" about global warming.

Gore, who had organised last month's Live Earth concerts and whose documentary An Inconvenient Truth won an Oscar, has not ruled out another bid for the US presidency.

"I haven't ruled out the possibility of running again at some point, but I don't expect to do so."