It is not hard to sum up what drives the wheat trade: exports go from temperate climates to tropical and from wet regions to dry. Since many dry countries have become dependent on imported grain to produce staple foods, there is little they can do but take the higher price on the chin.

Wheat is a thirsty crop. A kilogramme takes an average of 1,200 litres of water to grow, compared with 100-150 litres for 1kg of potatoes. Farmers in countries where there is a scarcity of water, such as Egypt (the world’s second biggest wheat importer), require irrigation to grow grains. It is much cheaper to import from wetter climates like the US and EU, where wheat farming requires only rainfall.