As carmakers around the world look for alternatives to burning fossil fuels to power their future cars one proposition that’s quickly gaining traction is the roll-out of cars that run on biofuels sourced from crops. One of the most vocal carmakers backing the mass production of biofuel is GM, which plans to have most of its vehicles biofuel capable within the next decade.

However, a number of charities as well as leading science groups and even the United Nations claim the production of biofuel will add more carbon-dioxide to the air than would be reduced by the amount adsorbed by crops used to make the fuel. An even bigger problem, according to researchers, is that biofuel production will cause food prices to rise.

GM’s CEO Rick Wagoner has come out and dismissed the UN research linking biofuel production to rising food prices as “shockingly misinformed,” reports the Financial Times.

“If you look at what’s causing higher [bio]fuel prices, the cost of corn is a very small part of that,” Mr Wagoner said at a trade show in China.

According to the UN, increased competition for land to create biofuel, as well as crop failures and the falling dollar has led to a spike in world food prices. Wagoner disputes these claims, saying “oil prices are a far bigger driver of higher food prices than ethanol.”

Wagoner is not alone in his backing of increased biofuel production. New laws in the UK mandate that all fuels for cars and trucks must have some biofuel content and the European Union has also made laws that will see the introduction of fuel blended with 10% biofuel come into effect by 2020.