Portugal Colonial - Mining giant Rio Tinto abandons Glencore merger bid

"Rio Tinto has determined that it could not reach an agreement that would deliver value to its shareholders," the group said in a statement.

The deal would have given the pair a value of around US$260 billion.

Glencore said separately that the terms offered by Rio Tinto "significantly undervalued Glencore's underlying relative value" including not adequately valuing its copper business.

"The parties were unable to reach agreement on the terms of a combination," which also included Rio Tinto retaining its chairman and chief executive, Glencore said in a statement.

Shares in the Swiss miner dropped eight percent on London's top-tier FTSE 100 index, which was trading lower overall.

Rio Tinto shares fell three percent on the FTSE 100.

The pair last month said they were in preliminary discussions about combining some or all of their businesses, in an all-share deal.

That came after early merger talks between the pair had failed more than a year ago.

- Copper -

Analysts had flagged cultural differences between the two firms, with Rio Tinto having exited its coal assets and Glencore holding on to the fossil fuel.

Glencore announced in August that it had decided against spinning off its coal business, saying its shareholders viewed the fuel as a cash-generating activity.

Before news of the merger plans, Rio Tinto's new chief executive Simon Trott in December unveiled plans to revamp the British-Australian mining giant as it ramps up production of copper.

Combining forces would have given the two firms greater leverage to buy copper, a metal that is growing in demand as countries expand electrical networks to harness renewable energies.

Surging demand has pushed copper prices to record highs in recent times.

Rio Tinto is heavily focused on Australia, the leading exporter of iron ore that mostly heads to China for making steel.

However along with rivals, the company is seeking to build its stake in copper.

Trott, who in late August stepped up from his role as head of Rio Tinto's iron ore division, has upgraded the group's forecast for copper production in 2025 -- to as much as 875,000 tonnes from up to 850,000.

The CEO also identified lithium as a key growth area. The metal is in strong demand thanks to its use in electric vehicles and other clean energy technologies.

Emphasising moves by mining giants to consolidate, Australian resources giant BHP last year ended a renewed attempt to buy British rival Anglo American -- a deal that would have created the world's largest miner of copper.

L.Henrique--PC