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Australian mining tycoon Andrew Forrest, founder and executive chairman of Fortescue, says it is time for the world to walk away from the "proven fantasy" of net zero emissions by 2050 and to embrace "real zero" by 2040 instead.

Speaking to CNBC's "Street Signs Europe" on Wednesday, Forrest called on business executives and politicians reluctant to make the changes necessary to avert the worst of what the climate crisis has in store to make way for leaders willing to take on the decarbonization challenge.

Fortescue, which is the world's fourth-largest iron ore miner, has outlined plans to stop burning fossil fuels across its Australian iron ore operations by the end of the decade — and urged other hard-to-abate companies to follow suit.

"All those leaders who say to me, say to the world, say to their kids, 'oh you know we can't do it, my company can't do it, I can't do it, you don't understand we can't actually do it,'" Forrest said in an exclusive interview.

"What they are really saying is that you can't do it. And I'm saying to each of those chief executives and those political leaders who use the words 'I can't,' OK, what about you get off the stage and let on a young girl or wiser leader who can. Someone with a bit of ticker because the technology is there," he continued.

"We know the world can go real zero 2040 and I'm reaching out to the business people and politicians across our planet to say it is time now to walk away from this proven fantasy [of] net zero 2050 and adopt real zero 2040," Forrest said. "We can, we must, let's do it."

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