The European Union's executive said it was looking at further measures to tackle the unwanted side-effects of biofuels production, which compromise the fuels' green credentials.
After a two-year investigation, the European Commission said the complex issue of "indirect land use change" could lessen carbon savings from biofuels, but it stopped short of immediately recommending new barriers against unsustainable biofuels.
Instead, it will recommend six months more of studies before announcing a new strategy next summer to compliment existing tough measures to ensure biofuels do not promote deforestation and push up food prices, which were set this June.