When it comes to the Democratic presidential frontrunner’s position on one of the most pressing issues facing humanity, author and journalist Naomi Klein isn’t mincing words: She says flat-out that she doesn't trust Hillary Clinton on addressing climate change.

"I don't trust her on climate at all," Klein told Al Jazeera’s Mehdi Hasan, in an UpFront interview scheduled to air on Friday, March 18. "As secretary of state, when she had a huge megaphone to make this an issue, to show that she understands the connections between human security and climate, she didn't use the megaphone."

Klein, a fierce critic of corporate capitalism, also questioned the rationale behind Clinton’s White House bid:

The logic of her candidacy was because she had so much money […] which is why she is unbeatable — look at how deep the pockets are there. But the irony is, it’s where that money comes from and the entanglement of the Clinton Foundation with so many corporations and so many governments, that is what makes her vulnerable. So on the one hand, it’s supposed to be what makes it inevitable, and on the other hand it’s what I think makes her a weak candidate.

She called Bernie Sanders a "significantly better candidate" than Clinton. "I think that Bernie Sanders could win in a general election," she said.

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