The UK Government is now facing calls for an urgent safety review of genetically-modified (GM) foods and a row is brewing in the scientific community over the apparent suppression of important research.

Dr Arpad Pusztai, 68, made a public statement about his fears last August. He was effectively forced to retire by the Rowett Research Institute after it accused him of misinterpreting his results.

But the group of scientists, drawn from 13 different countries, have re-examined his work and signed a joint memorandum supporting his conclusions.

GM crops: Moratorium requested

Speaking on BBC Radio 4's Today programme, Labour MP Alan Simpson said Dr Pusztai had been "completely vindicated" and called for a moratorium on GM food.

Last year, the doctor's £1.6m research project, funded by the Scottish Office, found that when rats were fed on GM potatoes for a period of 10 days, the development of certain vital organs was impaired and their immune systems suffered.

Reports in the press also says the size of the rats' brains decreased.

Speaking on BBC Two's Newsnight programme, group spokesman Dr Vyvyan Howard, a Liverpool University toxipathologist, said he believed Dr Arpad's data was "sound".

"We are at a loss really to explain why the Rowett Institute said what it did in the audit report, which was basically that there is nothing to report," he said.

'Thoroughly reviewed'

At the time of Dr Pusztai's comments, made on Granada Television's World in Action programme, the Aberdeen-based institute dismissed the doctor's conclusions as "misleading information" based on the wrong kind of potato.

Speaking for the governement, Cabinet "enforcer" Jack Cunningham told Newsnight that any new findings would be "thoroughly" reviewed, but added: "I would be very surprised if results which were considered to be not relevant work were suddenly validated by another set of experiments."

In a separate, but parallel development English Nature has written to Prime Minister Tony Blair asking for a moratorium on the use of herbicide-resistant GM crops until proper research into their potential long-term effects has been carried out.

If crops can be made more resistant to herbicides, scientific thinking holds that stronger - hence more efficient - herbicides can then be used to kill weeds in the area of those crops.

There are fears, however, that such crops could eventually damage biodiversity, because not only weeds, but valuable varieties of animal and insect would find the herbicides intolerable.