Overall volume dropped slightly as 84 contracts of 5 percent white rice were traded compared to Friday's 88. The most active January contract settled at 11.34 baht per kg, down from 11.36 baht, with the number of contracts traded rising to 48 from 3.
"The price of every contract declined as players liquidated them to avoid risks. They will stay sidelined until they see how prices move when the buying scheme was kicked off," said one broker.
The government usually buys rice from farmers at higher-than-market prices to support domestic prices when the main crop comes onto the market in November.
It has said it will buy 5 percent paddy grade at 7,100 baht ($174.2) per tonne. On the physical front, Thai 5 percent white rice was steady at 10.80 baht per kg.