The World Council of Churches has issued a hard-hitting appeal to Christians across the globe telling them that "the scandal of hunger demands the immediate attention of the churches".

The WCC's General Secretary the Rev Dr Samuel Kobia said in a statement on Thursday that he was "deeply concerned and outraged by this untenable situation", which sees an estimated 850 million people around the world going hungry each day.

Kobia urged churches "to formulate and implement programmes that seek to deal with hunger and its structural causes" as he warned that food security for all was "among the greatest challenges facing humanity". Among other initiatives, churches "are called to advocate against the production of agro-fuels at the expense of food production and the environment".

World leaders joined in a heated debate on biofuels at last week's major food summit in Rome, with the US and Brazil defending the use of maize and sugar cane to produce ethanol as car fuel, saying it was only a minor factor in food price inflation. Biofuel critics warn that the industry is diverting crops from food to cars at the expense of global food security.

Kobia applauded world leaders at the summit for their determination "in tackling the impact of climate change on food production and bio-energy, and confronting the challenges this situation poses to the achievement of global food security".

He said he hoped world leaders "may demonstrate their commitment to act against hunger and poverty and that this will lead to timely action".

The WCC statement claimed that the global food crisis had its "primary cause" in "inappropriate human actions, which have induced climate change and skyrocketing food prices".

Such actions were "driven by greed", Kobia affirmed, adding that a shift in the "prevailing development paradigm" was needed to break the reliance of food production and distribution on market forces.

"Humanity must be challenged to overcome its greed," he said.

Kobia announced that the WCC executive committee would address the food crisis at its next meeting in September 2008. He concluded that churches had an "essential role" to play and affirmed that they "must face the global food crisis together".