BANDAR LAMPUNG: Trade in Vietnam's coffee market ground to a virtual halt due to a lack of beans, while domestic prices in Indonesia fell this week as supplies continued to rise, traders said on Thursday.

Farmers in the Central Highlands, Vietnam's largest coffee-growing area, sold coffee at 32,000 dong ($1.38) per kg, unchanged from last week.

"There's almost no coffee left at the moment, so we can't sign new export contracts for delivery during the rest of the current crop year," said a trader based in the Central Highlands.

The current 2019/20 crop year will officially end at the end of September and farmers will start the new harvest in October.

September robusta coffee extended its rebound on Wednesday, settling up $17, or 1%, at $1,204 per tonne.

"But the London price is still too low. We could only make gains if it is above $1,250," the trader said.

Traders in Vietnam offered 5% black and broken grade 2 robusta at $200 premium per tonne for the September contract, down from $240 premium last week.

Meanwhile, Indonesia's Sumatran robusta beans are traded at $300 premium this week to the September contract, down from last week's $340 premium, according to a trader in Lampung province.

Higher supply due to harvests has helped keep prices down, aided by a stronger dollar against the rupiah, the trader said.

"Supply has increased this week, we are seeing double incoming beans than the previous weeks," the trader added.

Another trader said the premium remain unchanged at $350-$370 this week due to stiff competition from local buyers.

Indonesia exported 14,172 tonnes of robusta coffee beans in June from its province of Lampung on the island of Sumatra, trade office data showed on Wednesday.