Sen. Bernie Sanders (I-VT) said at a rally to promote the Green New Deal at Howard University in Washington, DC, on Monday night that climate change is an “existential threat” that, if not stopped will lead to “international havoc and war.”

Climate change, Sanders said, is considered around the world a national security issue “because if people cannot grow the crops they need, if people cannot find clean water to drink, there will be massive migrations of people all over the world. It will put increased pressure on limited natural resources and cause international havoc and war.”

Sanders joined Rep. Alexandria Ocasio-Cortez (D-NY), who introduced the Green New Deal resolution in February, at the rally. The proposal calls for a radical transformation of the United States economy and infrastructure, including ending air travel, cattle ranching, and fossil fuel production.

It also guarantees jobs and universal health care.

Sanders, who is running for the 2020 Democrat presidential nomination, also brought up a range of issues that aren’t linked to climate, including military spending, which he said funds “weapons on destruction.”

“Think about spending that money on making this planet healthy and habitable,” Sanders said, adding that climate change calls for a “global approach which emphasizes the Green New Deal.”

He also railed against the fossil fuel industry and its role in a “corrupt” political system but promised a “just transition” for workers in that industry who would lose their livelihoods if the Green New Deal were to be made into legislation and passed as law.

“If we are going to be honest about combating climate change, we have to understand that we have an overall economy that is rigged and a political system that is corrupt,” Sanders said.

Sanders praised the Sunrise movement for their climate change activism and called today’s youth the “most progressive generation in American history.”

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