A plan to increase the use of biofuels in Europe to be outlined next week may do nothing to help fight climate change and incur costs that outweigh the benefits, says an internal European Union report.

The unpublished study by the Joint Research Centre, the European Commission's in-house scientific institute, may complicate the Commission's meeting next Wednesday at which it plans to set a new biofuels target so that by 2020 they account for 10 per cent of transport fuels in the 27-member EU.