The long-term study, which was commissioned by the Austrian health ministry, found that female mice that had been given a diet consisting of 33 per cent genetically-modified (GM) maize had fewer babies and fewer litters than those fed on non-GM food after a few generations.

But the authors of the study were keen to point out that these were only initial findings and that further tests were needed to confirm the effect of GM foods on other animals and on humans.

'This is an isolated case and the results cannot in any way be applied to humans', the Austrian health and food safety agency AGES, which presented the study by Vienna's University of Veterinary Medicine (VUW) on Tuesday, said in a statement.

'Confirmation of these preliminary results is urgently needed through further studies', the study's author, Juergen Zentek, added.

Environmental groups like Global 2000 and Greenpeace were quick to seize on the study to call for a ban on all GM crops.

'Considering the severity of the potential threat to human health and reproduction, Greenpeace is demanding a recall of all GE (genetically-engineered) food and crops from the market, worldwide', the group said in a statement.

Distributing GM foods was 'like playing Russian roulette with consumers and public health', added Greenpeace's GM expert Jan van Aken.

EU Health Commissioner Androulla Vassiliou has requested a copy of the study and will then pass it on to the European food safety authority for expertise, her spokesman said. -- AFP