Anti-hunting campaigners have said they will seek the expulsion of pro-safari groups from the world's most authoritative conservation organisation after a report concluded that shooting big game for sport cannot be considered sustainable.

A report published on the website of the International Union for Conservation of Nature, the Swiss-based association that produces the globally recognised list of endangered species, said that "trophy hunting is not consistent with 'sustainable use'" of wildlife resources and countries and organisations that advocate it should be denied membership of the 71-year-old body.

It comes amid a bitter conflict within the conservation community between governments and organisations who see hunting as a conservation tool and those who consider it morally and scientifically unjustified.

Advocates say properly managed trophy hunting can help control wildlife populations, mitigate animal-human conflict, and create an economic incentive for local communities to protect endangered species rather than poach them.

The World Wide Fund for Nature, which is a member of the IUCN, says it does not oppose hunting programmes that do not threaten the survival of species and are part of a demonstrated conservation strategy.

But the report, which appeared on the IUCN website last week and was written by professors of environmental law from six countries, concluded that the economic and conservation benefits of trophy hunting were questionable at best and that the continued membership of hunting advocates undermined the IUCN's claim to "moral and ethical leadership" in conservation.