The drive towards self-sufficiency in response to last year’s food crisis will fail, a top executive at Cargill has warned, adding that the idea that countries “can be self-sufficient in every single food is a nonsense”.

The warning by the world’s largest trader of agricultural commodities comes ahead of the UN World Summit on Food Security in Rome, the first since 2002. The summit was prompted by the surge in the price of staples such as rice and wheat, which last year hit record highs, sparking food riots in countries from Bangladesh to Haiti.