The renewed focus raises questions around the big miner’s local aluminium smelters, which Rio unsuccessfully investigated floating last year under the Pacific Aluminium moniker.

Rio’s new aluminium head, Alfredo Barrios yesterday told investors that Rio would embark on a new strategy. “In the next few years, we will be transforming our business around our two key pillars, our industry leading bauxite assets and world class first-quartile smelting position,” he said.

Rio’s bauxite assets are focused in Australia, where export expansions at Gove in the Northern Territory and Weipa in Queensland are being looked at.

The miner’s lowest-cost smelters were bought in the debt-funded $US37 billion Alcan acquisition in 2007, which caused Rio big problems when credit markets froze in the global financial crisis.

Yesterday, Mr Barrios indicated the company could try to sell aluminium capacity that is not in the least expensive quartile of global operations if they can’t shape up. “For those 20 per cent (of Rio’s capacity) which aren’t in the first quartile, the pathway has been defined to try to get there in the next few months,” he said.

“We will make a decision on the way forward for those that do not meet the guidance.”

Mr Barrios assured investors he was looking for “value-accretive” options. “We are not looking to divest these assets if that destroys value for our shareholders.”

The more expensive smelters that had been earmarked for a spin-off include the Boyne Smelter at Gladstone, the Tomago smelter in the Hunter Valley and the Bell Bay smelter in Tasmania.

At Weipa, Rio has been spruiking its long-slated next development, known as South of Embley, which is tipped to replace and expand on output from Weipa.

Mr Barrios said Rio was investigating a first-up development that could export 22.8 million tonnes of bauxite a year, with a secondary expansion to bring that to 50 million tonnes.

But Rio chief Sam Walsh said there could be scope for changes to this and did not rule out doing the big expansion in one go. “We are looking at every option we have in terms of optimising the project,” he said after being asked whether Rio could pursue a “big bang” expansion to 50 million tonnes.

The project is expected to go to the board for approval next year.

When asked about Glencore at the briefing, Mr Walsh raised the spectre of the ill-fated Alcan acquisition, which many believe was done as a defensive move against a looming bid from BHP Billiton.

“We are not looking at any major M&A; we are not looking at doing anything stupid, we are looking at playing our game plan,” he said when asked if Rio’s pledge to strong shareholder returns was being fuelled by Glencore interest.

Mr Walsh said previous comments to news agencies that Rio had a different culture to Glencore did not mean a merger was out of the question.

“The questions being asked are really for (Glencore chairman) Tony Hayward and his board,” he said, avoiding mention of Glencore’s major shareholder and billionaire chief Ivan Glasenberg, when asked if his comments on culture meant a merger was out of the question.