The price of iron ore appears to have stabilised after Monday's sharp 4 per cent fall, but it has still yet to see a positive session in the past nine.

At the end of the latest session, benchmark iron ore for immediate delivery to the port of Tianjin in China was trading at $US53.10 a tonne, down 0.4 per cent from $US53.30 a tonne in the prior session.

Investors are cautious given persistent worries about the Chinese economy as well as an imminent shutdown of steel mills near Beijing for a World War II parade.

Chinese news agencies have reported a push to curb air pollution around Beijing by as much as 40 per cent would see steel mills and other facilities near the capital closed from August 28 to September 4.

The last time a similar event occurred -- November last year -- steel output slid 6 per cent on the month.

"Compared to 'APEC Blue' in November 2014, the area affected by 'Parade Blue' is even bigger, suggesting that the impact on production could be deeper, especially among heavy industry," Jianguang Shen, economist at Mizuho Securities, said.

There is a suggestion the recent stability in the price of iron ore was driven by a ramp-up in steel production ahead of the parade, with the risk iron ore demand cools significantly over coming weeks.

The activity, or lack thereof, comes after BHP Billiton warned of further market volatility in announcing its full-year results on Tuesday.

“Although China’s steel exports are at an all-time high, we expect subdued crude steel production growth over the remainder of the 2015 calendar year, with some upside potential should the construction sector recover,” BHP chief executive Andrew Mackenzie said.

"In the short term, we expect ongoing economic reforms in China to contribute to periods of market volatility.

"And, while we remain confident in the long-term outlook for commodities demand as emerging economies continue to urbanise and industrialise, we have lowered our forecast of peak Chinese steel production to between 935 million tonnes and 985 million tonnes in the mid 2020s."