SIR – High food prices are a serious problem across the world. People on lower incomes in the UK are having to cut back their weekly grocery shopping, while in poorer countries high food prices can be a matter of life and death.

The changing climate and the increasing use of food crops for biofuels are part of the problem. But banks are also culpable. Financial speculation by banks and hedge funds is fuelling food price rises, often pushing them much higher than supply and demand can explain.

I’m taking part in a campaign by the World Development Movement calling for strict regulation to curb food speculation. We need to make sure that the finance sector stops making easy money at the expense of hungry people. Food is too important to be subject to reckless financial gambling.

Maureen Wakelin, Roydscliffe Road, Bradford