BANGKOK Thai exports unexpectedly rose for the first time in 11 months in August, helped by higher shipments of agricultural and industrial goods, despite weak global demand, the commerce ministry said on Tuesday.

Customs-based exports, a key driver of Thailand's economy, rose 2.6% in August from a year earlier, compared with analysts' median forecast for a 4% decline in a Reuters poll.

In August, Thailand posted a trade surplus of $0.36 billion, compared with a forecast deficit of $1.75 billion, while imports dropped 12.8% year-on-year. That compared to a fall of 10% seen in the poll.

In the January-August period, exports contracted 4.5% from year earlier.

Exports are expected to contract by up to 1% to 2% this year, Deputy Commerce Minister Napintorn Srisanpang said this month.

(Reporting by Kitiphong Thaichareon and Orathai Sriring; Editing by Martin Petty)