Geneva, Oct. 21 (Reuters): The world is consuming some 20 per cent more natural resources a year than the planet can produce, conservationist group WWF has warned.

Urging governments to move rapidly to restore the ecological balance, the Swiss-based group said rich countries, particularly in North America, were largely to blame for the situation.

?We are running up an ecological debt which we will not be able to pay off,? Claude Martin, the director-general of WWF International, told a news conference.

In its Living Planet Report 2004, the fifth in a series, the WWF said that between 1970 and 2000, populations of marine and terrestrial species fell 30 per cent. That of freshwater species declined 50 per cent.

?This is a direct consequence of increasing human demand for food, fibre, energy and water,? it said.