Recent heavy rains in Thailand, Vietnam, Cambodia and Laos have destroyed or put at risk 3.7 million acres of paddy rice fields, according to Agence France-Press news agency. Thailand, the world's top rice-exporting nation, has lost nearly 1 million hectares (2.4 million acres) of rice — or 10 percent of its annual production, according to Thai government officials.

Meanwhile, Vietnam, the world's No. 2 rice-exporting nation, has been heavily affected by flood waters draining from Laos and Cambodia into Vietnam's Mekong Delta, which accounts for half of the country's rice production. Pakistan, the third-largest rice exporting country, has also been impacted by flooding, with losses estimated at nearly $2 billion.

According to Margareta Wahlstrom, the United Nations chief of disaster reduction, "the whole region will now suffer from rising food prices as potential harvests have now been devastated. The damage is very serious this year and it will be some time before people can resume normal lives."

In addition to the flood damage, the Thai government's new rice support policy, which will pay Thai farmers above market prices for rice, is reportedly stoking fears among some market observers that global rice prices may rise.