By Kate Kelland

LONDON, March 14 (Reuters) - Europe's stringent regulation of genetically modified crops has no rational basis and should be revamped to allow countries who want to opt out and grow GM foods to do so, British scientific advisers said on Friday.

In an advisory report requested by the government, the scientists said legislation on use within the European Union (EU) of genetically modified organisms (GMO) in crops should be decided on a national level, as it is with pharmaceuticals.

"Technology for making crops healthier and more environmentally friendly is moving on fast, but the regulatory system needs to change to allow us to take advantage of this benefit sooner," said Jonathan Jones, a GM expert at Britain's Sainsbury Laboratory and one of the authors of the report.

Many countries in the EU have populations who are hostile to growing GM crops. In Britain, too, there is likely to be public opposition to the idea, with campaigners arguing the long-term consequences of having widespread GM agriculture are unknown.

Yet the vast majority of scientists argue GM modification in crops is just as safe as conventional crop breeding, and can bring with it great benefits in terms of creating plants engineered to resist disease, fight off pests and endure unstable or stressful weather conditions.

In a letter to Prime Minister David Cameron, the scientists said that while the EU "is currently hostile to growing GM crops" Britain "can still benefit significantly in developing innovations that the rest of the world will still use" if it is able to argue for national control over GM decisions.

No GM crops are currently grown commercially in Britain, and only two - a pest-resistant maize and a potato with enhanced starch content - are licensed for cultivation in the EU.

British GM crop experts say EU regulations add between 10 and 20 million pounds ($16 million to $33 million) to the cost of developing a GM trait in a crop - prohibitive for the public sector and for small and medium sized businesses.

TRAITS

In the United States, where there is far less opposition to GM crops, the first GM seeds were planted more than 15 years ago and so far no evidence has been documented of adverse health impacts for people eating GM-derived foods.

Speaking at a briefing in London, the UK scientists said they endorsed the view of the European Academies Science Advisory Council (EASAC), which has said there is no rational basis for the current stringent process for GM crops.

EASAC represents 29 scientific bodies across the region.

David Baulcombe, chair of the UK report's working group and Head of Plant Sciences at the University of Cambridge, said most public concerns about GM crops have nothing to do with the technology, which he said is as safe as conventional breeding.

"They are more often related to the way that the technology is applied," he said, "and whether it is beneficial for small scale farmers or for the environment".

For that reason, EU regulations need to be adapted to focus on the traits of the GM crops - such as their pest-resistance or enhanced yield - rather than on the genetic modification method itself, the scientists argued.

This is the approach taken in regulating pharmaceuticals - where regulators look at the effects that new drugs have on patients not at the technology used to develop them, which in many cases also involves genetic modification, they said.

Mark Walport, Cameron's chief scientific adviser, praised the report and said he was sure the prime minister would welcome its advice. He acknowledged, however, that it was likely to face some public opposition and prompt argument within the EU.

"There will be a discussion. We live in a plural society, and people are going to have strongly held views about this," he said. "We have to have a clear and rational debate about the science itself." (Editing by Janet Lawrence)