China's move to open trading in iron ore futures to foreign investors has drawn a guarded reaction from Australia's major mining companies. Greg Navarro has more from Sydney.

GREG NAVARRO SYDNEY Iron ore plays a crucial role in Australia's economy, and tops its list of exports - most of it goes to China. There seems to be a guarded reaction so far from the major mining companies about the impact of China's decision opening up trading of iron to foreign investors. The head of mining company Fortescue reportedly said the company, quote "supports pricing mechanisms which accurately reflect supply and demand for iron ore and provide certainty for the industry". One analyst I spoke with said that you can expect volatility by outside speculators - because they tend to drive prices higher and lower on par. As for how the major mining companies here will react, there seems to be a sense of waiting to see the initial impact of the move. It's important to note the impact that iron ore and mining in general has had on Australia's economy. The mining boom helped protect the country from the impact of the global financial crisis. Since then, Australia's economy has relied less on mining - but it, and iron ore exports, still play an important role. Greg Navarro, CGTN, Sydney.