Anglo-Australian miner Rio Tinto has announced that China's state-owned Chinalco is to invest a further $19.5bn in the business.
Commodity prices have fallen sharply since last summer
The move - China's largest investment in a foreign company - could see Chinalco increase its stake in Rio to 18% from the current level of 9%.
The news came as Rio reported a 7% fall in its 2008 profits to $9.2bn.Global commodity prices hit record highs last summer before falling back sharply as the world economy slumped.
Rio called the move a "pioneering partnership", but some analysts say there is likely to be concern among those who feel it gives China too much control over the world's supply of raw materials like iron ore.
The BBC's Theo Leggett outlined the details of the deal.
Listen Hear Theo Leggett's report (1 min 32 secs)
End of Section
Underlying reasons
Some analysts have also questioned the timing of the deal, seeing as it comes at a time when commodity prices are low because of the weak global economy.
However, BBC business editor Robert Peston said this was only one way in looking at the announcement, and that in other respects Rio had got a good deal.
So, what's led the Chinese to take this expensive step? Our Shanghai correspondent Chris Hogg explains.
Listen Hear Chris Hogg's analysis (1 min 50 secs)
First broadcast on World Business News on 12 February 2009
End of Section
Rio Tinto explains
Anlaysts say that one of the things which the global crisis has done, is to lay bare bare a new world order. Broadly, Americans and other developed countries borrowed to spend while China and others saved and sold. They argue that it was an unsustainable imbalance which is now collapsing.
Business Daily's Steve Evans asked Rio Tinto's chairman, Paul Skinner, what the Chinese would get for their money.
Listen Hear Rio Tinto chairman Paul Skinner
End of Section
