Pope Benedict urged all Christians on Sunday to help international efforts to resolve a food price crisis that threatens to make millions more people go hungry, ahead of a food summit in Rome early next month.

"Whoever is nourished by the bread of Christ cannot remain indifferent before those who, in our times too, are deprived of daily bread," he said, referring to the Christian Eucharist where bread and wine represent the body and blood of Christ.

"This problem is getting more and more serious and the international community is struggling to resolve it," said the German-born pontiff in his regular Angelus address to pilgrims at St Peter's Square in Rome.

The United Nations' Food and Agriculture Organisation hosts a summit in Rome on June 3-5 to discuss the difficulties caused by record-high commodity prices, which have doubled the food import bills of the poorest countries in the past two years.

With food protests and riots already seen in some developing countries, the summit will discuss the impact on food security of climate change and biofuel use, which has switched millions of tonnes of cereals from food to fuel production.