Rio said its board decided a takeover would not have been in the best interests of its shareholders.

On Monday, speculation of a possible merger had caused shares in Rio Tinto to rise by more than 9 per cent in New York.

The mining giant now has a market capitalisation of nearly £56.3bn compared with Glencore’s £44.5bn. A deal would have created the world’s largest publicly listed mining group.

In a statement, Rio Tinto confirmed it was approached by Glencore in July about a potential merger, but the board unanimously rejected the proposal in early August.

“There has been no further contact between the companies on this matter,” the statement said. “Rio Tinto remains focused on the successful execution of its strategy, which the board of Rio Tinto is confident will continue to deliver significant and sustainable value for shareholders.
 
Rio Tinto chairman Jan du Plessis added: “The board believes that the continued successful execution of Rio Tinto’s strategy will allow Rio Tinto to increase free cash flow significantly in the near term and materially increase returns to shareholders. Rio Tinto’s shareholders stand to benefit from the very considerable value that this will generate.