Source: Sharecast
It said: "Rio Tinto assessed the opportunity and came to this view through the disciplined lens set out at its capital markets day in December 2025 - prioritising long-term value and delivering leading shareholder returns."
For its part, Glencore said the key terms of the potential offer were Rio Tinto retaining both the chairman and chief executive officer roles and delivering a proforma ownership of the combined company. This "significantly undervalued Glencore's underlying relative value contribution to the combined group, even before consideration of a suitable acquisition control premium", it said.
"We concluded that the proposed acquisition on these terms is not in the best interests of Glencore shareholders.
"It does not reflect our view on long term, through the cycle relative value, including not adequately valuing our copper business, and its leading growth pipeline, and apportioning material synergy value potential."
Glencore insisted that its standalone investment case is strong. "We have a well-diversified business across a range of commodities, supported by one of the best marketing franchises in the industry," it said.
"We are uniquely positioned to support the energy needs of today whilst providing many of the transition enabling commodities the world needs as demand changes."
At 1600 GMT, Glencore shares were down 8% at 469.15p, while Rio was 2.6% lower at 6,826.30p.
Danni Hewson, head of financial analysis at AJ Bell, said: "Many wondered whether it might be third time lucky when Rio Tinto and Glencore got back around the table to discuss a deal which would have created the world’s biggest mining company - but today it emerged it was not to be.
"Statements from both companies hinted at the gulf between the two despite months of back-and-forth discussions. It had been thought that Rio Tinto’s new CEO might bridge the cultural differences between the two companies and succeed in getting the mega merger over the line. But with so much at stake and shareholders to appease, it seems ultimately the magic number couldn’t be found, at least not right now.
"There’s been considerable momentum in the mining sector as demand for metals like copper ramps up amid an ongoing shift to cleaner energy technology. It’s therefore understandable that the spectre of consolidation keeps popping up, but so far deals have been hard to strike."