The EU's food safety agency challenged its doubters on Monday, making available all the scientific information used to clear a genetically modified corn which a French researcher had linked to cancer.

The European Food Safety Authority said that "given the level of public interest ... (it would) make all data on genetically modified (GM) maize NK603 publicly available on its website."

While EFSA had previously provided such information on request, "any member of the public or scientific community will now be able to examine and utilise the full data sets used in this risk assessment," it said in a statement.

EFSA, which reviews the use and authorisation of such crops and foodstuffs, in November rejected outright a report by Gilles-Eric Seralini of the University of Caen which had linked NK603 to cancer found in laboratory rats.

It said at the time that Seralini's work failed to meet "acceptable scientific standards" and accordingly it had no reason to review its assessment of NK603, made by US agri-food giant Monsanto.

The EU also demanded that Seralini release more details of his work but he responded in kind, calling on EFSA to open up its data first.

The EFSA said on Monday that the NK603 data was being made available as part of an initiative to make its overall workings more transparent.

"Risk assessment is an evolving science and EFSA is always willing to review its past work should new robust science bring a new perspective to any of the (its) previous findings," EFSA Executive Director Catherine Geslain-Laneelle said in a statement.

Monday's move "aims to make data used in risk assessment publicly available," Geslain-Laneelle said, by promoting research and working with scientists.

"This will make the conclusions of risk assessments even stronger when ensuring public health protection and further build confidence in EFSAs work."

Environmental groups have been very critical of the EFSA, saying it was not doing enough on its own to test GM foods and gave Monday's announcement a guarded welcome.

"This sounds like a positive initiative to shine some light on the secretive world of EU GM crop authorisations," said Greenpeace EU agriculture policy director Marco Contiero.

"So far, EFSA has only published information on one specific GM product. We expect that the same level of transparency will apply to all GM products that have been and will be submitted for EU approval," Contiero said in a statement.

"Confidential business information will continue to be kept secret, so it will be crucial to see how wide a definition EFSA will choose to use."