The decline in China's monthly trade surplus could be short-lived as the upcoming holiday season is likely to boost world demand for China-made products, according to experts.

Although the September figure fell nearly 3.5 billion U.S. dollars from the August level to 15.3 billion dollars, it is still the second highest of the year and more than twice the figure of last September, official statistics revealed.

Researcher Li Jian with the Institute of Research under the Ministry of Commerce said the September slowdown was "normal".

The slowdown was mainly due to the appreciation of the yuan and the removal of export tax rebates for energy-guzzling and environmentally costly commodities, Li explained.

France-based BNP Paribas, an investment bank, also regards the September decline as just a blip on the screen. Its latest report projects an increase of more than 30 percent each month for China's exports in the fourth quarter, as well as a monthly increase of 20 percent for imports.

Ben Simpfendorfer, Asia Strategist with the Royal Bank of Scotland, said intensive purchasing before Christmas would lift China's monthly surplus to a new high.

Citing electronic goods as an example, he said products ordered for the fourth quarter are now being shipped from China.