His government ordered a review of the environmental and economic effects of biofuels production in February.

"We need to look closely at the impact on food prices and the environment of different production methods and to ensure we are more selective in our support (for biofuels)," Brown said in a statement.

"If our UK review shows that we need to change our approach, we will also push for change in EU biofuels targets," he said.

The EU's executive Commission said on Monday it stood by its target of getting 10 percent of road transport fuel from crops and agricultural waste by 2020, despite criticism it could contribute to food shortages.

UN Secretary-General Ban Ki-moon warned on Sunday that higher food prices risked wiping out progress towards reducing poverty and, if allowed to escalate, could hurt global growth and security.

Price rises have led to riots in Asia and Africa. In rich countries such as Britain, rising food costs are straining family budgets, making it a political issue for Brown whose popularity has slumped.

Brown called earlier this month for a coordinated response led by the United Nations, the World Bank and the International Monetary Fund to the price rises.

He has convened a meeting of experts, including World Food Programme head Josette Sheeran, on Tuesday to develop proposals that he plans to present to the European Union, the Group of Eight leading industrialised countries and the United Nations.

Also attending the meeting will be Donald Kaberuka, head of the African Development Bank, Justin King, chief executive of British retailer J. Sainsbury and representatives of Swiss agrochemicals group Syngenta Cargill Grain Traders, charity Oxfam and the National Farmers' Union.

Brown called for more research into higher-yielding crop varieties that can withstand harsh climates and for an agricultural revolution in developing countries.

A global trade agreement that opened up markets in rich countries and cut farm subsidies was also needed, he said.

He said the world was now "inches from" a deal in long-running trade talks, saying this could spur food production in poor countries.