At least 29 countries have sharply curtailed food exports so they can maintain food supplies at affordable prices for their own citizens, the newspaper said Monday. India, Vietnam, China and 11 other nations have limited or banned rice exports, and 15 countries, including Pakistan and Bolivia, have curtailed or halted exports of wheat.

The limits on food exports are contributing to growing hunger in poor nations, especially among people who rely on relief agencies for food. Pascal Lamy, director general of the World Trade Organization said export restrictions "fuel the fire of price increases."

The restrictions on food exporting in other nations has helped feed a perception of shortages, leading to hoarding by farmers, traders and consumers.

Thailand, Brazil, Canada and the United States are among the handful of nations that still export large quantities of food, the newspaper said.