Genetically modified (GM) food is an essential tool to help tackle the "perfect storm" of climate change and rising population, the Government's chief scientist has warned.

Professor John Beddington said the world will have to produce 50 per cent more food by 2030 in order to feed the growing population.

He said the only way to do this is to grow more crops on less land by using the latest scientific innovation, including crops genetically modified to be drought or disease resistant.

"This is such a problem that you cannot say we will not use GM technology - that would be really unwise," he said.

His comments come as a new Royal Society report also recommends GM crops to tackle the impending food crisis.

The report entitled 'Reaping the Benefits: Towards a Sustainable Intensification of Global Agriculture' is expected to suggest that GM crops could even be grown in Britain.

GM has recently come back onto the political agenda. The first trial in a year was recently re-started in Leeds, with the Government's support, and a recent report on food security from the Deparment for the Enviroment, Food and Rural Affairs backed further research into the technology.

But environmentalists insist the science is not proven and foods made from GM crops or "Frankenstein Foods" may be bad for human health.

Speaking at a global food summit, organised by the not-for-profit environmental research centre CABI, Professor Beddington said science will be the only way to feed the world in the future.

He said that by 2030 the world will have to produce 50 per cent more food and energy, together with 30 per cent more available fresh water, whilst adapting the floods and drought caused by climate change.

Prof Beddington said Britain could lead the way in developing the new technology - although he said it would be difficullt to grow GM crops in Britain because of activists ripping up the plants.

"Ten years ago, when GM was first started, people were understandably worried about about health and environmental impacts. But I think current regulations mean those risks are now mitigated," he said.

Dr Julian Little, Chairman of the Agricultural Biotechnology Council, said 13 million farmers are already growing GM on 125 million hectares around the world.

"If we are serious about producing more food off less land, we do not have much choice but to use new biotechnology, including GM," he said.

But Clare Oxborrow, Senior Food Campaigner with Friends of the Earth, said the Government was in danger of being blinded by "the white heat of technology" and putting human and environmental health at risk.

"We do have a 'perfect storm' with the impending food crisis, climate change and the recent economic crisis," she said. "It might seem like the perfect opportunity for the bio-tech industry to promote its products but the drivers of this crisis are so complex and need to be tackled at a fundamental level - just the thought that GM can solve this or play an important part is pie in the sky."