China’s imports and exports slumped again in August, authorities said Tuesday, the latest setback for the world's number-one trader in goods, as European businesses urged authorities to accelerate reforms to avoid stagnation in the giant economy.

The figures come as a growth slowdown in China's economy -- whose demand for commodities and status as a vital market make it a key driver of the world economy -- has sent panic through global markets.

Beijing is trying to rebalance to a more sustainable economic model where expansion is predominantly driven by domestic consumer demand rather than exports and investment, but the transition is not proving easy, a situation exacerbated by weak demand in some of China's major markets.

The European Union Chamber of Commerce warned in an annual report that "slow" implementation of market reforms risked plunging the country into stagnation.

Chinese authorities are targeting year-on-year growth of around six percent in two-way trade this year. Instead it fell by 9.1 percent overall in August, measured in dollar terms, Customs said.

"Exports to the US and the Association of South-East Asian Nations continued to grow but shipments to the EU and Japan declined," Customs said on its website.

Exports fell 5.5 percent year-on-year to $196.9 billion in August, it said.

The drop, though, was significantly less than the median forecast of a 6.6 percent decline in a survey of economists by Bloomberg News, and also an improvement from July's 8.3 percent fall.

Imports fell 13.8 percent year-on-year to $136.6 billion, Customs said, attributing the decline to widespread commodity price falls.

It was the 10th consecutive monthly fall in import values, and worse than both the Bloomberg survey's projection of a 7.9 percent decline, and July's 8.1 percent drop.

"Globally everyone has had a very, very weak period of exports and economic growth," said Jefferies Group strategist Sean Darby.

"It's not just China, but also Taiwan, Korea, and most of Asia and emerging markets. China gets the focus because it's the biggest, but in reality, no one is having a very good time out there."

China's trade surplus was $60.2 billion last month, Customs said, without giving the change in dollar terms. It earlier said that measured in China's yuan currency the surplus had risen 20.1 percent.

- 'Still weak' -

But Julian Evans-Pritchard of Capital Economics said the outlook was "brighter than many believe".

"The deeper contractions in headline trade growth will undoubtedly be viewed by some as further evidence of a deteriorating economic outlook for China," he said in a reaction.

"But we think the apparent weakness is misleading," he added, citing a high comparative base from last year for exports and commodity price deflation weighing on imports.

"Trade growth ought to recover over the coming quarters," he said.

Authorities have stepped up efforts to bolster growth, with the central bank last month reducing interest rates for the fifth time since November.

They also lowered the yuan's central rate against the US dollar by nearly five percent in a single week, which should make Chinese exports cheaper on world markets.

"The narrowed drop in exports is a positive signal that government support measures to exporters have been working," Li Daxiao, chief economist at Yingda Securities, told AFP.

"But the weak import figure showed that the economy is still on the weak side and the government has to step up its stabilising efforts to maintain the seven percent growth target."

The Chinese government is aiming for growth of "around seven percent" this year. Expansion stood at 7.0 percent in each of the first two quarters this year, according to official figures, but on Monday the 2014 growth statistic was lowered to 7.3 percent, from the 7.4 percent announced in January.

Global stock markets have been roiled by worries over slowing growth in China, whose own exchanges have plummeted as a debt-fuelled bubble burst.

The benchmark Shanghai Composite Index edged up 0.10 percent, or 3.08 points, to 3,083.50 in afternoon trade on Tuesday.

Communist authorities have promised to give market forces the "decisive role" in the economy, but in its annual report the European Chamber said China's "markedly slow progress" was "very unsettling for business".

Implementing change has taken on an "urgency with the economy slowing down", its president Joerg Wuttke told AFP.

"It is sometimes disappointing to see how little this derives into real time action.

"It would be terrible if they would waste a crisis. The stagnation of Japan should be a warning of where China could end up."