Stuart Kirk has resigned from his role as global head of sustainable investments at HSBC Global Asset Management, claiming the firm's behaviour has made his position "unsustainable".

In a post on LinkedIn, Kirk (pictured) blamed the conduct of HSBC since his Miami speech in May and asserted that he had enjoyed a 27-year "unblemished record" across his roles in finance, journalism and consulting up until this moment.

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He also took a parting swipe at both HSBC and the ESG movement across finance:

"Investing is hard. So is saving our planet. Opinions on both differ. But humanity's best chance of success is open and honest debate. If companies believe in diversity and speaking up, they need to walk the talk. A cancel culture destroys wealth and progress.

"There is no place for virtue signalling in finance. Likewise as a writer, researcher and investor, I know that words or trading shares can only achieve so much. True impact comes from the combination of real-world action and innovative solutions."

He added that the "mainstream bubble" of sustainable finance suffered from "nonsense, hypocrisy, sloppy logic and groupthink".

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Kirk used his resignation to promote a vague new project aiming to deliver "the greatest sustainable investment idea ever conceived" through the work of a "crack group of like-minded individuals", which would create an entirely new asset class.

Referencing his speech, Kirk said: "To be announced later this year, the first project will underline the central argument in my speech: that human ingenuity can and will overcome the challenges ahead, while at the same time offering huge investment opportunities."