"The Asian financial crisis has created a detrimental impact on China's foreign trade this year, which is expected to become fully evident in the fourth quarter this year and next year," said Wu, who has a foreign trade portfolio.

"It's still hard to reach a conclusion on how big the impact could be," she was quoted as saying.

Customs figures showed China's exports dipped a 6.7-per cent during the year to September, the biggest annual fall shown in any single month this year.

That was compared with a 24-per cent annual surge in exports in the same month last year.

The Asian crisis has slashed demand for Chinese goods in the region.

China's exports declined in May this year for the first time in nearly two years, bounced back in June and July but sank again in August.

Despite slowing exports, China posted alarger-than-expected trade surplus of $35.3 billion in the first nine months of this year thanks to weak imports.

China recorded a trade surplus of $40.3 billion in 1997, when exports grew 20.9 per cent from the previous year.

Wu urged trading firms to further diversify overseas sales.

China's exports this year have been largely underpinned by booming sales to the United States and Europe. Customs data showed shipments to the United States rose 16.5 per cent in September and that to Europe surged 21.7 per cent.

Wu called on trading firms to "try every possible way" to expand overseas sales, sell more hard currency earnings to banks and curb illegal arbitrage of foreign exchange.

Chinese authorities have in recent weeks unveiled tough measures aimed at stemming capital flight that reflects a lack of confidence in the yuan.

To boost exports, Beijing has raised export rebates on a wide range of products, including nonferrous metals and textile products.