The Australian dollar traded little changed on the news, with the drop in surplus offsetting optimism over the upbeat exports and imports numbers.

Combined, they brought the country's trade surplus to $31 billion from a record high of $49.8 billion in August, short of analysts' forecast for a reading of $41 billion.

Imports unexpectedly rose 7 percent, versus forecasts for a decline of 2.7 percent and following a fall of 2.4 percent in August.

Exports surged 15.3 percent in September from the year-ago period, data showed on Monday, beating the 11.8 percent gain expected in a Reuters poll and after rising 9.4 percent in August.

China's exports grew at a stronger-than-expected pace in September, but focus appears to be imports, which defied expectations of a decline, a sign that domestic demand may be on the mend.

"The strength in imports was a surprise, and suggests that the sharp growth deceleration in August has been arrested," economists at Barclays, wrote in a note. "Imports registered strong growth from commodity intensive countries, with shipments from Asean, Russia and South Africa up strongly.



"Today's data add more weight to our view that growth will recover sequentially in the fourth quarter," they added.



There have been concerns about slowing domestic demand in the world's second biggest economy, which has been exacerbated by a downturn in the property market. Chinese authorities have repeatedly warned that the trade sector may miss their growth target of 7.5 percent this year.

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Analysts say the trade picture may improve further going into the year-end, boosted by demand during the festive holiday season.



"A lot of stuff that we buy today is still made in China. What we saw over the past months, inventories have run down to relatively low levels...[but] don't forget we are going into the year-end Christmas season so I wouldn't be surprised to see a bit of a pickup in China export numbers," said Daryl Liew, head of portfolio management at REYL.

But Julian Evans-Pritchard, China economist at Capital Economics warned against reading too much into the traditionally-volatile data.

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"Although import growth also rebounded, this should not be taken as a sign that domestic demand growth is turning a corner," he said.



"The strength seems to have been driven by a surge in imports for processing and re-export. As such, it mostly reflects a brighter export outlook rather than a pick-up in domestic demand. Sharp falls in commodity prices, along with slowing investment, appear to have continued to weigh on the value of commodity imports last month," Evans-Pritchard added.