The Philippines has spent about $1.54 billion this year buying 2.3 million tons of rice mainly from Vietnam and Thailand to fill a gap in local production and increase its stockpile.

The amount is close to three times last year's rice import bill of $626 million.

Volume at 2.3 million tons is more than half a million tons more than last year's 1.87 million tons imported.

The National Food Authority said it had to import more due to low buffer stocks and a larger-than-anticipated production shortfall.

The Philippines imports about 10 percent of its annual rice supply requirement. Despite increases in its annual output of the grain, production has not kept pace with a rapid growth in the country's population, now estimated at around 89 million.

The Philippines consumes about 32,000 tons of rice a day, according to a government study.

Vietnam has exported 2.54 million tons of rice since the start of this year, up 2 percent from the same period last year, leaving less than 1 million tons to be shipped through September under a government curb.

Vietnam has capped rice exports from January to September at 3.5 million tons, but officials have said shipment by the year-end could hit 4.5 million tons, similar to 2007 when Vietnam was the world's third-largest exporter of rice after Thailand and India.

Rice exports during the first 18 days of July totalled 242,700 tons, bringing the cumulative shipment so far this year to 2.54 million tons, the Vietnam Food Association said in its weekly report.

It said revenues of the grain exports had reached $1.42 billion, nearly double revenues of $723 million from 2.49 million tons shipped in the same period last year. Vietnam has projected rice export earnings of $3 billion for the whole of 2008.

Most of Vietnamese rice exported so far this year has gone to the Philippines, the world's larges importer of the grain.

Vietnam has won contracts to sell about 1.6 million tons of rice to the Philippines via tenders and which are considered government deals.

This has left trading firms little room for their own contracts due to the government's export limit.

Given the 2.54 million-ton shipment and 10,000 tons sold to an European trader for shipment to Iraq, exporters and trading firms share between themselves 950,000 tons for deals between now and the end of September.

Part of the remaining 950,000 tons is already reserved for the Philippines and also Cuba, which has an annual arrangement with Vietnam to buy 200,000 tons each year in various shipments.

Dim prospects of securing a large export deal and a harvest in the Mekong Delta food producing area that is now in full swing have caused domestic prices to ease.

Summer-autumn paddy prices edged down to between 4,700 and 4,800 dong (28.4-29 US cents) per kg on Monday in the Delta, about 3 percent down from between 4,800 dong and 5,000 dong a week ago.