BENGALURU: Indian export rice prices fell to their lowest in more than two months this week due to a weaker rupee and muted demand, while mounting supplies from an ongoing harvest weighed on Vietnamese rates.

Top exporter India saw rates for its 5% broken parboiled variety fall to $366-$372 per tonne, the lowest since March 26, from $368-$373 last week.

The rupee has fallen more than 6% this year, prompting exporters to cut rates.

"Even after lowering prices, there is no improvement in demand," said an exporter based at Kakinada in the southern state of Andhra Pradesh.

India's rice production could surge to a record as farmers are expanding the area under paddy because of good monsoon rains.

Demand weakened for Vietnam rice as well, with rates for the country's 5% broken rice slipping to $450 per tonne, the lowest in nearly two months. Prices had hit an eight-year high of $475 on June 4 as rains hampered harvest.

"Demand from foreign buyers has weakened this week," a trader based in Ho Chi Minh City said.

Domestic supplies are building up amid the summer-autumn harvest, other traders said, adding that Vietnam could export 2.3-2.5 million tonnes from the harvest after securing enough for local consumption.

Prices of Thailand's benchmark 5% broken rice eased to $505-$525 a tonne on Thursday, from $505-$533 last week, with traders attributing the slip to a stronger Baht.

"Demand remains flat because our prices are higher than India and Vietnam," said a Bangkok-based rice trader.

Concerns over supply lingered after a drought hampered production earlier this year.