Prince Charles told world leaders Monday at the United Nations Climate Change Conference (COP26) that the world stands on “warlike footing” with the threat of climate change.

Prince Charles has long advocated for bolder climate-change measures. In 2007, he founded the Prince's Mayday Network, which involves businesses committed to battling climate change.

He warned Monday that time has “literally run out” to galvanize world leaders into action.

“Climate change and biodiversity loss are no different,” Prince Charles said. “In fact, they pose an even greater existential threat to the extent that we have to put ourselves on what might be called a warlike footing.”

In September 2020, Prince Charles called for a “Marshall-like plan for nature, people, and planet.”

The conference is taking place in Glasgow, Scotland, from Oct. 31 to Nov. 12. The U.K. official website for COP26 reads that the event will “bring parties together to accelerate action towards the goals of the Paris Agreement and the UN Framework Convention on Climate Change.”

The Paris Agreement is a legally binding international treaty that aims to “limit global warming to well below 2, preferably 1.5 degrees Celsius, compared to pre-industrial levels.”

Prince Charles also invoked the COVID-19 pandemic, which he said proves “just how devastating a global, cross border threat can be.” He also advocated for collaboration between nations, for “countries to come together to create the environment that enables every sector of industry to take the action required.”

Prince Charles also warned that the spending necessary to transition into a sustainable, green economy will require trillions of dollars, not billions.