Vietnam, which will be less affected by drought because its rice fields are along river basins, will export more white rice.
Drought conditions will also trim Thailand's opportunity to ship new grains.
Shipments of Thai Hom Mali fragrant rice are expected to fall to 1.8 million tonnes this year from 1.99 million in 2015 because demand for premium rice in the world market is expected to fall given the global economic slowdown.