BENGALURU, March 19 -- Thailand's rice export rates extended gains this week to hit a 6-1/2 year peak, and Vietnamese prices rose to their highest in almost 16 months, as the spread of the coronavirus raised concerns about sufficiency of available stocks.

Thailand's benchmark 5% broken rice prices were quoted at $480-$505 per metric ton on Thursday, their highest since August 2013 and up from $470-$495 last week. This is also their sixth consecutive weekly rise.

Traders said market concern over supply shortages due to the ongoing drought was the main factor driving up prices.

"Some millers are stockpiling rice as domestic concern rises over food shortage in case the outbreak of coronavirus gets worse," a Bangkok-based rice trader said.

"There is no demand because of the high prices, and as supply becomes less and less, I think prices will get even higher."

Domestic demand for some rice types, such as jasmine, has increased slightly over consumers' concerns about the widening spread of the virus, traders said.

In Vietnam, rates for 5% broken rice rose to $410 per metric ton, the highest since November 2018, from $400-$405 a week earlier.

"Domestic supplies are thin, and exporters are finding it hard to secure rice for their contracts," a trader based in Ho Chi Minh City said.

"Farmers are not selling their rice, as they fear the coronavirus outbreak will last for a long time."

Preliminary shipping data showed 195,400 metric tons of rice is to be loaded at Ho Chi Minh City port between March 1-25, with most of the rice heading to Malaysia, West Africa and Cuba.

The Vietnamese government on Wednesday said it will ensure an annual rice output of 22 million metric tons.

In India, export prices were steady, near their lowest in over two months, as export demand improved slightly amid a depreciation in rupee to a record low.

India's 5% broken parboiled variety was quoted $363-$367 per metric ton this week, unchanged from last week.

Indian rupee was trading near a record low on Thursday, raising exporters margins from the overseas sale.

Local broken rice prices could moderate in the coming weeks as demand has been falling from the poultry industry, said Nitin Gupta, vice president for Olam India's rice business.

Chicken sales have plunged on rumors that chickens were spreading coronavirus.

Domestic prices of rice have risen by up to 5% in Bangladesh, as coronavirus fears triggered panic buying.

Food Minister Sadhan Chandra Majumder urged people not to panic as the government has sufficient stocks of food-grains.