Some global shares and commodity prices have plunged, fuelled by fears of a slowdown in China.

China’s official news agency Xinhua declared “Black Monday!” on Twitter as its stock market fell by almost 9 per cent – the biggest one-day drop since 2007.

As a result, the Australian stock exchange dropped just over four per cent, while the US Dow Jones industrial average was 3.55 per cent down at the closing bell.

• Australian shares slump as Chinese stocks plunge
• Future risk of shonky economics
• Super funds warn members to expect lower returns

Several European markets fared worse, with Germany’s blue-chip DAX 30 index falling 6.79 per cent, France 6.57 per cent and Norway more than 7 per cent. Amsterdam, Brussels, Milan and Madrid also fell more than five per cent.

London’s benchmark FTSE 100 index of leading companies lost 5.02 per cent.

“It is a China-driven macro panic,” ABN Amro chief investment officer Didier Duret told the ABC.

“Volatility will persist until we see better data there or strong policy action through forceful monetary easing.”

Chinese stocks have continued to tumble since mid-June, despite the government’s attempts to restore confidence.

China-linked shares led the global sell-off, with Shanghai closing down 8.49 per cent, the biggest daily loss since February 27, 2007.

Falling oil prices weighed on market sentiment as they slid below $US40 a barrel for the first time since 2009, after weak Chinese manufacturing data deepened fears that the Asian giant is growing more slowly than thought.

Global equities lost more than $US5 trillion since China’s shock currency devaluation on August 11.

Crisis-hit Greece’s main stock market plummeted more than 11 per cent, succumbing to a Chinese-led sell-off and also domestic political uncertainty ahead of likely elections next month.

The euro meanwhile strengthened to $US1.1599 from $US1.1386 on Friday.

Russia’s rouble also hit a new 2015 low and stocks sank, battered by falling oil prices and the impact of sanctions over Ukraine.

Data on Friday showed Chinese manufacturing activity slowed to a 77-month low had added to the gloom, signalling that even a campaign by Beijing with its vast arsenal of reserves has not been able to stimulate growth.

In other top Asian markets, Hong Kong’s benchmark fell 5.17 per cent, Tokyo 4.61 per cent, and Sydney lost 4.09 per cent.

More than 800 stocks listed in Shanghai fell by their maximum 10 per cent daily limit, among them many of the brokerages that spurred a year-long rally that saw shares soar 150 per cent before they collapsed in June.

Chinese authorities have since launched unprecedented measures to support stocks. On Sunday state media said the huge national pension fund would now be allowed to buy equities, in a fresh bid to prop up the market.

But local investors fear even Beijing’s huge firepower will not be enough to stop the rout in Chinese shares, particularly after the benchmark Shanghai index fell through the key 3500 point mark.