MAJOR beef producing countries with a history of "mad cow'' disease will have to wait for up to two years to find out if they can export beef to Australia.

Biosecurity Australia today announced it had initiated formal quarantine assessments of beef from the US, Canada and Japan to establish the risks of importing bovine spongiform encephalopathy or any other animal diseases.

BA chief executive Dr Colin Grant said the import risk analyses would take up to 24 months to complete, involving preparation of draft reports, extensive public consultation, an expert specialist panel to help with scientific issues, and scrutiny by the independent Eminent Scientists Group.

The move comes in the wake of the Federal Government's controversial decision late last year to scrap blanket bans on beef imports from BSE-affected countries after a scientific review found there was little risk of humans contracting the brain-wasting disease from eating beef from these countries.

The ban was lifted from the start of last month with a requirement that food safety checks would be conducted before imports could commence.

But there was uncertainty about whether the disease risks for Australia's beef cattle would also be part of the approval process, with critics of the move concerned about the threat to Australia's ``clean, green'' reputation.

Last month Federal Agriculture Minister Tony Burke requested that BA conduct formal regulated IRAs on beef from countries other than New Zealand in parallel with the food safety assessments being done by Food Standards Australia New Zealand.

Existing requests for access to Australia from the US, Canada and Japan, lodged before the BSE ban was lifted, were now being given high priority, Dr Grant said.