Famed activist investor Chris Hohn ripped into one of the ESG industry’s most popular strategies, known as “engagement,” characterizing it as all talk and no meaningful action.

“We should stop pretending and just be honest,” the chief executive of TCI Fund Management said on Thursday at the Bloomberg Intelligence ESG Investment Forum in London. “The acid test is actual emissions, are they falling or are they rising? And they’re rising. And that’s where the rubber hits the road.”

Using engagement strategies, investment managers have been able to defend holdings in everything from fossil-fuel producers to companies that rely on child labor in supply chains, by pointing to their efforts to engage with management. But there’s little in the way of policing of such claims and asset managers often have inconsistent approaches.

Hohn, who donates to Extinction Rebellion and has channeled billions of dollars of his personal fortune into a children’s investment fund he created, said he can’t see any evidence that engagement actually works. His assessment, therefore, is that “there’s obviously a collective failure happening” in the ESG investing world. He went so far as to evoke remarks by climate activist Greta Thunberg, who famously derided politicians for producing little more than “blah, blah, blah” in response to the climate emergency.

Hohn, whose firm last year marked its 13th straight year of profits with a 23% return, said fund managers need to use more powerful strategies than engagement, and said TCI is currently filing resolutions demanding that corporate boards “explain and justify” why they’re not able to live up to short-term climate goals.

Fund managers touting engagement strategies are coming under increasing pressure to prove their methods yield results. In recent months, there’s been an additional wave of skepticism triggered by revelations that many ESG funds held stakes in everything from Russian government bonds to state-backed oil and gas giants.

“The heart of the issue for me, from my experience of 25 years investing is what Greta Thunberg calls blah, blah, blah, talk, talk, talk, engage, engage, engage achieves nothing. Nothing, nothing, nothing,” Hohn said.

Market researcher Morningstar Inc. said last month it’s conducting a review of the fund industry to make sure managers are applying meaningful engagement strategies.

“We are going to look at engagement more closely, engagement activities related to climate especially, to hold managers to account,” Hortense Bioy, global head of sustainability research at Morningstar, said in an interview in April.

Bioy has previously said that managers who allow their engagement strategies to drag on for much longer than two years have some explaining to do. The Morningstar review comes after a major purge conducted earlier this year, when Bioy cited “ambiguous” ESG definitions as grounds to strip the label off funds representing more than $1 trillion.

Hohn even suggested that fund managers who don’t produce evidence that their ESG engagement strategies are working should lose their jobs, “because they’re not performing.”

The ESG industry has now surpassed $40 trillion in value, according to Bloomberg Intelligence. In a March 8 report, the International Energy Agency said that global CO2 emissions rebounded last year to their “highest level in history.”

United Nations Secretary-General Antonio Guterres warned in March that the planet is currently “sleepwalking” toward a “climate catastrophe.”

Hohn said “people should wake up.”

“All this engagement isn’t achieving anything,” he said. “We’re deluding ourselves, our asset owners and our children if we pretend that engagement is actually achieving anything. It isn’t.”

--With assistance from Nishant Kumar.

This article was provided by Bloomberg News.