Biofuels have driven up food prices worldwide by 75%, according to the UK's the Guardian newspaper, citing an unpublished report from the World Bank.

The newspaper said today (4 July) that it had gained access to the World Bank study, which was completed in April but is yet to be published.

The analysis from the World Bank suggests the push to ramp up biofuels production in the US and EU has pushed up food prices by 75% - far more than governments on both sides of the Atlantic have claimed.

The newspaper claimed that the report has yet to be published in order to avoid embarrassment for President George W. Bush, a firm advocate of biofuels production in order to cut US dependence on imported oil.

Critics of the push for biofuels, including a swathe of food industry groups, have blamed the alternative fuels for rising food prices around the world, as corn is diverted from food production.

G8 leaders will meet in Japan next week to discuss the global food crisis and have faced intense pressure to call for a moratorium on biofuels production.

Officials at the World Bank offices in London could not be reached for immediate comment.