Global rice supplies are under threat amid fears over decimated crops in Thailand, the world’s largest rice exporter.

Thailand is currently suffering its worst drought in two decades and its rice output is likely to have been badly hit when the crop cycle finishes in August.

Production could fall to just two million tons from the five million previously forecast, according to the Thai Rice Mills Association.

The country’s Royal Irrigation Department predicted farmers “would be lucky” to see one monsoon storm during this year’s annual rainy season – significantly down on the average three to four storms that normally occur a year.

Thailand exports around 9 million metric tons of rice a year.