The extinction crisis facing the world's wildlife could be even worse than previously thought, according to the latest analysis of species under threat.

Conservationists who analysed the International Union for Conservation of Nature (IUCN) Red List of threatened species said that despite global pledges to halt wildlife declines by 2010, governments were not reversing the downward trend.

The IUCN urged leaders to put as much effort into saving nature as they did into economic rescue packages, as countries were "utterly dependent" on the diversity of animal and plantlife.

The report analyses 44,838 species on the IUCN Red List, revealing 869 species are extinct or have vanished from the wild, while a further 290 are possibly extinct.

At least 16,928 of the species on the list are threatened with extinction.

But as only 2.7% of the world's 1.8 million known species are on the Red List, this could be just the tip of the iceberg.

The analysis - carried out once every four years on the Red List - revealed that birds, mammals, amphibians and corals all show a continued deterioration in extinction risk.

And an examination of 17,000 species showed that 30% of birds, 41% of amphibians and 51% of reef-building corals which are currently not threatened could be susceptible to the effects of climate change.

The report also showed that almost two fifths (38%) of freshwater fish in Europe were under threat, while at sea more than a quarter of marine birds (27%) and the same proportion of reef-building corals are threatened with extinction.

Craig Hilton Taylor, co-editor of the study said: "The report makes for depressing reading. It tells that the extinction crisis is as bad, or even worse, than we believed."