The Chinese government was today handed a seat at the mining industry's top table by a desperate Rio Tinto which was forced to sell prized assets to state-owned Chinalco in a exchange for an injection of nearly $20 billion (£13.9 billion) cash.

Some Rio shareholders reacted with fury to the deal, which one described as "giving away the crown jewels".

It has been the most controversial fundraising since Barclays' deal to raise cash from Arab investors last year, and could cost Rio chairman Paul Skinner the job he had lined up as the next chairman of BP.

Chinalco, which is pouring $19.5 billion into the London and Sydney-listed mining giant, has bought in at what many see as the bottom of the cycle. In return it gets bonds which will convert into shares and eventually see Chinalco owning 18% of the company - double its current stake.

Chinalco will get two seats on the board and big stakes in Rio's crown jewels including the Grasberg copper-gold mine in Indonesia and a 15% stake in its Hamersley Iron division.

Earlier this week, chairman-elect Jim Leng quit after less than a month in the job due to his disapproval of the Chinalco deal.

One angry investor said: "We told Jim Leng it is better to raise money from us rather than selling the crown jewels."

Another, Warren Staude at Taurus Funds Management, said: "They think they can sell less than a controlling interest in their assets and still control them. They think they will still rule the roost and have money in the tin but that seems crazy."

The widely-flagged deal overshadowed Rio's annual results, which were better than expected with a 38% rise in underlying profit of $10.3 billion for 2008.

Net profit tumbled 50% to $3.7 billion, hit by asset impairment charges of $8.4 billion. These were only partly offset by asset sales worth $1.5 billion.