The WWF's Living Planet Report, published every other year, said the natural world was being degraded "at a rate unprecedented in human history".

The report, released on Tuesday, showed relentless growth in demand on the earth's capacity to produce clean air, and to provide raw materials, food and energy.

James Leape, WWF's director-general, said: "We are in serious ecological overshoot, consuming resources faster than the earth can replace them. The consequences of this are predictable and dire.

"The cities, power plants and homes we build today will either lock society into damaging over-consumption beyond our lifetimes, or begin to propel this and future generations towards sustainable living."

Energy consumption

Two years ago, the same report based on 2001 data said the world's population was already outstripping the earth's capacity to regenerate resources by just over 20 per cent.

The 2006 edition of the WWF report said that figure had risen to 25 per cent in 2003.

The WWF said carbon dioxide emissions from energy consumption were the fastest growing component of the index in that period, increasing more than ninefold.

A survey of animal life from 1970 to 2003 found that terrestrial species had declined by 31 per cent, freshwater species by 28 per cent and marine species by 27 per cent.

The WWF estimated that even a rapid reversal in consumption habits now would only bring the world back to 1980s levels, when it was already over-consuming, by 2040.

The United Arab Emirates (11.9 hectares per person) and the United States (9.6) again came at the top of the Living Planet's ranking of the environmental impact of countries, largely due to high energy consumption.

Finland and Canada overtook oil-producing and consuming Kuwait to take third and fourth place in the table.

Climate security threat

Meanwhile, Margaret Beckett, the UK foreign secretary, will warn Europe on Tuesday to tackle climate change or risk terrorists seizing on famine, water shortages and failing energy infrastructure to threaten global security.

In her first major foreign policy speech, to a group of experts

Water shortages will cripple
poorer countries

in Berlin, Beckett will call on the European Union to lead a global push towards new technologies and renewable energy, warning EU countries are already "dangerously behind the curve".

Beckett is expected to cite reduced rainfall in the Middle East as a possible trigger for security problems.

She will argue climate change, with drastically diminishing resources in some of the most volatile parts of the world, has the potential to create a "potentially catastrophic dynamic" in regions already at breaking point.

Beckett, a former environment minister, will say the Middle East is a case in point as climate models suggest Saudi Arabia, Iran and Iraq will be among those countries to see the biggest rainfall reductions in the world.

Egypt, a pivotal country for regional stability, will suffer a double blow, she will say, as loss of flow from the river Nile and rising sea-levels in the north are set to destroy the country's agricultural heartland.