Genetically modified food may be the only way for farmers to feed a growing world population, a former European commissioner has warned.

Mariann Fischer Boel, (corr) who retired last year after five years as EU Commissioner for Agriculture and Rural Development, raised the controversial topic in a speech at the Kent County Show. She said GM had to be considered "whether we like it or not."

She told guests at a lunch hosted by the president of Kent County Agricultural Society, the show organisers, that the world's population was expected to grow from seven billion to nine billion by 2050 and this posed a huge challenge to producers, especially as global diet was likely to become more Westernised, with more meat and dairy products.

"Farmers and food producers will have to deliver this under pressure from competition and ever more volatile markets," she said. "They will have to do so by adapting to the effects of climate change and contributing at the same time to the cutting of greenhouse gases and emissions, so new technologies and innovations will be essential to the agricultural sector."

She conceded that biotechnology was a "touchy" area, but warned: "You have to be aware of the fact that if we want to be able to increase our production by between 70 and 100 per cent, GMO [genetically modified organism] will be an issue whether we like it or not." But she added that taking advantage of the new technology meant using it in the right and responsible way.

She called on farmers to take practical steps to keep feeding the world. Action had to be taken now if the dream of food security did not become a nightmare.