Customs data on Saturday showed exports at their most sluggish in two years — stripping out the volatile month of February. Import growth also slowed, reinforcing the weakening trend revealed in a slew of key Chinese economic indicators on Friday and signaling tough times ahead.

"We expect export growth to drop in the first half (of 2012) as external demand weakens," economists at Nomura said in a note to clients, forecasting that GDP growth in the first quarter of next year could slip to 7.5 percent, with deteriorating exports compounded by softening domestic demand.

The trade data paint a darkening picture for investors in the world's second largest economy. Exports expanded 13.8 percent year on year in November, while import growth slowed to 22.1 percent from October's year on year rise of 28.7 percent.

Economists in the benchmark Reuters poll forecast annual export growth of 11 percent in November and a 19 percent rise in import growth, with a trade surplus of $14.3 billion.

The surplus turned out to be $14.5 billion, narrowing from October's $17.0 billion and the same level as in September.

The trade data reveal the twin challenges stemming from Europe, where a festering debt crisis is destroying demand in China's single biggest trading partner and triggering capital flight from emerging markets as nervous investors opt instead for more traditional safe haven assets.

Europe remains China's single largest export market year-to-date, the destination for 18.9 percent of Chinese exports. But export growth to the continent slowed to just 5.0 percent in November from a year ago, the third straight month of single digits and smallest expansion since February 2011.

Exports to the United States over the same period totaled 17.1 percent, while those to the 10-member Association of Southeast Asian Nations (ASEAN) were 8.9 percent and exports to Japan were 7.8 percent of the total.

The picture wasn't all bad to Shen Jianguang, chief economist with Mizuho Securities Asia in Hong Kong, who was reassured by signs of a pro-growth shift of emphasis in government economic policy.

"China has clearly shifted its top priority to protect growth to engineer a soft landing of the economy," Shen said.

"Export growth has not collapsed yet, but things can get harder in the first half of next year when the export growth will probably slow below 10 percent in some months."

But it was the proportion of exports that went to Europe in November — 17.8 percent — that was significant to Chen Gang, a strategist with Oriental Securities in Shanghai, who noted it was the first time in five years it had been below 18 percent.

"There is little potential for China to increase its exports to Europe and the United States, so emerging markets will become more important for China," Chen said.

The trade data reinforced a slowing trend in the world's No. 2 economy, after key indicators on Friday showed a serious risk of a sharp industrial slowdown — accompanied by an easing of inflationary pressure — that is prompting Beijing to provide more support for growth and jobs.

China surprised investors on Nov. 30 with an earlier-than-expected cut in banks' required reserves, the first such move in three years, signaling a policy shift, although in words China has so far maintained its official line of sticking to a "prudent" monetary policy.

And the Communist Party's top leaders said in a statement hours after Friday's data deluge that they would ensure stable and reasonably fast economic growth in 2012, fine-tuning policy in tandem with changes in the global economy.

Such changes have triggered some signs of capital flight from emerging markets, largely inspired by Europe's crisis.

China's yuan currency has not been immune.

Official data revealed the first capital outflow from China in four years in October and the currency has hit its daily depreciation limit in each of the last eight trading days.

"The only recent comparable episode with such strong sell-off pressures, measured by the number of days that the close rate touched the depreciation limit, was back in early December 2008 when the world financial market was hit by a severe liquidity crunch following the collapse of Lehman Brothers," Ren Xianfang, senior China analyst at IHS Global Insight wrote in a note to clients.

Much could depend on how investors view Europe's Friday agreement to draft a new treaty for deeper economic integration with uncertainty lingering around when more decisive action would be taken to stem a crisis threatening France and even economic powerhouse Germany.

Mizuho's Shen though was more sanguine about the currency, which has gained about 40 percent in real effective terms since a landmark reform in 2005 to break its peg to the dollar.

"Expectations of yuan depreciation are temporary and will not change the long-term trend of a stronger yuan," Shen said. 

That's good news for China's leadership, which has pledged to increase imports in a bid to balance its trade account and cut its surplus. A stronger currency makes that job easier.