The President of the European Commission Jose Manuel Barroso has asked for an investigation into whether the push for biofuels is to blame for rising food prices.

The Commission seems in the process of shifting away from its previous unbridled support for the technology. It emerged last weekend that the Commission may cancel its target of requiring ten per cent of petrol and diesel to be biofuel by 2020.

Barroso said he wanted a study on all aspects of the issue: "The impact on prices, the impact on agriculture, on development... all aspects." Barroso made the comments last week following a meeting with the Belgian prime minister.

Recent weeks have seen riots over food prices in Egypt, Haiti, Indonesia and Mauritania. The UN's World Food Programme has said it needs an extra $755m to maintain its core budget against rising prices. Rice prices have hit record levels this year and several countries have banned exports - India has renewed a ban on all exports of non-basmati rice.

A spokesman for the President told EU Observer that the comments did not mean the ten per cent target for biofuels was being abandoned. "It is simply for the president to look at the data on a possible link with food prices."

There have been other signs of division within the Commission on the issue, one official described the ten per cent target as "now secondary".

In the UK Whitehall is also reviewing biofuel targets. British motor fuels are currently required to have 2.5 per cent biofuel content.

Apart from the impact on food prices biofuels are also criticised for providing less than claimed reductions in CO2 - much Western production of biofuel crops is dependent on fertilisers, and the processing of crops also emits a lot of carbon.