World shares have sagged as investors feared fresh rate cuts in China may not be enough to stabilise its slowing economy or halt a stocks collapse that is wreaking havoc in global markets.

Europe's main stock markets, which had surged on Tuesday after China's moves, reopened two percent down on Wednesday morning as the jittery mood returned and sent investors back into safe-haven German and United States government bonds.

China's key share indexes had attempted to move higher several times during Asian trading only to be slapped back by waves of selling, reflecting investors' views that much more support was needed from the government and the central bank.

Analyst: Expect more volatility in China

The Shanghai Composite Index on Wednesday closed 1.27 percent down on the previous day at 2927.29, amid fears of more volatility.

The country's benchmark has fallen dramatically from a 12-month high of more than 5000 points in June, more than 40 percent of its value, causing panic in markets across the globe.

China's central bank reduced interest rates and slashed the amount of money banks need to hold in reserve on Tuesday, its second such double move in two months, in a bid to bolster slowing growth.

The measures are not only expected to help boost cash flow in China, but also revive confidence that Beijing can steer the world's second-largest economy away from a hard landing and keep global growth on course.

The cuts initially fuelled a rebound in global equities, with European shares surging after their heaviest losses since the 2008 financial crisis on Monday, but optimism had fizzled by the end of US trading and Wall Street finished down.

Since a year-long, debt-fuelled rally collapsed in June, Beijing has unleashed unprecedented measures to support the market, including using state-backed vehicles to buy up shares.

While the slump in Shanghai may have a limited impact on the broader economy, worth about 13 percent of world output, it reflects dissipating confidence among investors that the sky-high valuations of quoted companies are warranted.

Source: Al Jazeera And AP