Rio Tinto has deferred billions of dollars of spending on decarbonisation projects as higher-than-expected costs at Guinea’s $US23.2 billion ($35.4 billion) Simandou iron ore project pushed the miner towards an expensive new growth phase.

Rio will raise total spending to $US30 billion over the next three years as chief executive Jakob Stausholm aims to increase the production of iron ore, copper and aluminium.