Among the leaders participating in a virtual climate and energy meeting hosted by the White House Friday morning is a man who has become the voice of climate activists worldwide, UN Secretary-General António Guterres.

Driving the news: Guterres, who will deliver virtual remarks to the Major Economies Forum (MEF) on Energy and Climate, will portray further investments in fossil fuels as "a danger" and implore leaders to swiftly change course.

Why it matters: Guterres has carved out a distinctly different role on climate compared to his predecessor, Ban Ki-moon. Instead of a bridge-builder, Guterres acts as a truth-teller and champion of climate activists and developing country residents who are acutely aware of the present-day damages from climate change.

• Friday morning, Guterres will tell leaders, "The first duty of leadership is to protect people from clear and present dangers. Nothing could be more clear or present than the danger of fossil fuel expansion," according to a copy of the speech.

Yes, but: Given the energy crunch in the wake of Russia's unprovoked invasion of Ukraine, Guterres is swimming against the tide in trying to speed up climate action now.

The big picture: Guterres's speech to the MEF comes as gas prices have eclipsed $5 per gallon in the U.S. and there is domestic political pressure to deemphasize the White House's climate goals in favor of short-term fossil fuel expansion.

• The war has sent Europe scrambling for alternate sources of natural gas for next winter while trying to hasten its long-term transition away from fossil fuels.
• Meanwhile, other countries, such as China, are consuming more of Russia's oil and gas, and are also turning back to coal, the most greenhouse gas intensive fuel, to generate electricity.
• Watchdog groups warn that these developments are further endangering the Paris climate targets.

Zoom in: Against the backdrop of these geopolitical headwinds, Guterres has issued increasingly dire warnings associated with climate science reports and addressed recent confabs in Davos and the Austrian World Summit.

• His statements are not subtle, and while they often travel far in the press they can fail to move some world leaders.

What they're saying: "Even in the short-term, fossil fuels don’t make political or economic sense," Gutteres will tell leaders from 23 nations today. "Yet we seem trapped in a world where fossil fuel producers and financiers have humanity by the throat."

• A senior UN official told Axios that today's speech will be free of diplomatic niceties. Describing the remarks, the advisor stated: "Even given the Secretary-General’s impressive track record of speaking truth-to-power, this is [a] blistering intervention, to the leaders of the world’s largest economies."

Of note: The MEF meeting will be the first time the UN leader will compare the past tactics employed by the oil and gas industry to mislead the public about the consequences of its products with those of the tobacco industry, the senior UN official said.

• "For decades, the fossil fuel industry has invested heavily in pseudo-science and public relations — with a false narrative to minimize their responsibility for climate change and undermine ambitious climate policies," Guterres will state. "They exploited precisely the same scandalous tactics as Big Tobacco decades before."

Meanwhile... At the MEF meeting, Biden and international partners will put forward a new initiative to tackle methane emissions leaks from the oil and gas sector, and projects to advance clean tech investment and work to decarbonize marine shipping.

• China's chief climate negotiator Xie Zhenhua will represent that country, which is currently the world's biggest emitter, at the MEF.