India refused to grant permission Wednesday for the commercial cultivation of its first genetically modified (GM) food crop, citing problems of public trust and "inadequate" science.

Environment Minister Jairam Ramesh said he was imposing a moratorium on the introduction of an aubergine modified with a gene toxic to pests that regularly devastate crops across India.

"It is my duty to adopt a cautious, precautionary, principle-based approach and impose a moratorium on the release," until scientific tests can guarantee the safety of the product, said Ramesh.

However, he added there was still no agreement among scientists on what constitutes "an adequate protocol of tests".

Ramesh said the moratorium was effective immediately and it would last "for as long as it is needed to establish public trust and confidence."

"I cannot go against science but in this case science is inadequate," he added. "I have to be sensitive to public concerns."

Indian regulators had approved the new aubergine back in October and its introduction would have made it the first GM foodstuff to be grown in India.

But the decision roused huge opposition and a broad spectrum of voices, including farmers, environmentalists and politicians of all stripes had urged the government to prevent its cultivation.

Ramesh spent the months since the decision travelling across the country holding public consultations with citizens.

Backers of the genetically modified aubergine said the product would boost yields by up to 50 percent, while reducing dependence on pesticides.

But critics pointed to possible long-term health problems, and warned it would open the doors to a flood of other GM food crops.

Mathura Rai, the Indian scientist who led the group that came up with the modified aubergine, declined to comment directly on the moratorium, but insisted that GM crops had a crucial role to play.

"We need a technology for increasing the quality production of vegetable crops," Rai, head of the Indian Institute of Vegetable Research, told AFP from his headquarters in Varanasi city.

"In certain areas where traditional methods of breeding is not possible to improve the production or productivity, biotechnology can play a vital role," he said.

"So this is the best option for increasing the production of quality aubergine in the country," he added.

The government's decision on Tuesday came at a sensitive time with growing public frustration over soaring food prices, following a particularly poor 2009 monsoon.

But Ramesh said there was "no overriding food security argument" for the introduction of GM aubergines.

He said he had considered the views of different interest groups in making his decision but denied he had been pressured by members of his cabinet or by companies producing genetically modified crops.

"My conscience is clear. This is my decision and my decision alone," he said.

India is one of the largest aubergine producers globally.

The seeds had been developed by local scientists but would have been marketed by an Indian company partly owned by the US multinational Monsanto.

India already allows the use of genetically modified cotton and supporters say it has sharply improved yields.