The United Nations Environment Programme says the developed countries must cut their use of natural resources by 90% to give the rest of the world a chance of emerging from poverty.

This radical prescription is part of UNEP's Global Environment Outlook 2000, an end-of-century review compiled by experts from more than 100 countries.

GEO-2000's key finding is stark: "The continued poverty of the majority of the planet's inhabitants and excessive consumption by the minority are the two major causes of environmental degradation," it says.

"The present course is unsustainable, and postponing action is no longer an option.

"A ten-fold reduction in resource consumption in the industrialised countries is a necessary long-term target if adequate resources are to be released for the needs of developing countries."

Realistic

The Director of UNEP, the former German Environment Minister Dr Klaus Toepfer, spoke to BBC News Online before launching the report in London.

Asked about the practicality of a ten-fold consumption cut, he said: "I am absolutely convinced that it is realistic.

And excessive consumption is the other

"This is not to go back to the middle ages, it is not to give the signal that austerity will be the solution.

"It is simply a question of what are the repercussions of our leisure society, of changing our day-to-day lives, of the urbanisation process.

"These are not visionary ideas, these are a must for a world with a year-by-year population increase of up to 80 million people."

GEO-2000 says 200 scientists in 50 countries identified water shortage and global warming, which it says "now seems inevitable", as the world's two most worrying problems.

The spread of the deserts and the loss of the forests were also key concerns.

No time left

It says there have been some success stories, notably the world's co-operation in tackling the depletion of the ozone layer, and the beginnings of work on tackling climate change. But it does not think the future will be easy.

"Despite successes on various fronts, time for a rational, well-planned transition to a sustainable system is running out fast. In some areas, it has already run out.

Global warming 'now seems inevitable'

"In others, new problems are emerging which compound already difficult situations."

One new problem identified in the report is the excessive use of nitrogen as a fertiliser.

"Human activities have doubled the amount of nitrogen available for uptake by plants. Unfortunately, half of all nitrogen applied to plants in the form of fertilisers is lost to the air or dissolved in water.

"We are fertilising the earth on a global scale and in a largely uncontrolled experiment," says the report.

Damage to children's brains

Nitrogen emissions contribute 6% of the greenhouse effect, and are involved in water contamination, air pollution, and the growth of algal blooms which kill aquatic life.

And the report says: "Nitrogen run-off from fertilisers can lead to brain damage in children".

It notes: "The environment remains largely outside the mainstream of everyday human consciousness, and is still considered an add-on to the fabric of life".

In calling for the integration of environmental thinking into the mainstream of decision-making, it echoes many similar pleas.