AS Rio Tinto and Chinalco position themselves to renegotiate their contentious $US19.5 billion ($25 billion) asset stake and convertible bond deal, a Rudd government ruling is looming.
Treasurer Wayne Swan is due to rule on the deal in the next three weeks.
However, changes to the deal will be needed to make it acceptable to Rio shareholders both here and in Britain after recent improvements in capital and debt markets.
If, in an unlikely scenario, Mr Swan demanded that a new application be delivered and took the maximum four-month period to rule on it, the decision would come too close for comfort to the October deadline for Rio to pay back $US8.9 billion of its debt.
However, any changes demanded by shareholders -- such as restricting state-owned Chinalco's stake to below 15 per cent in a capital raising -- are also expected to be more acceptable to the Foreign Investment Review Board.
People who have been through the board's approvals process before were loath to speculate on where the process could go and said that nothing was certain.
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