Two of the nation’s best-known progressive lawmakers are set to propose a bill to declare the climate crisis an official emergency.

Sen. Bernie Sanders (I-Vt.) and Rep. Alexandria Ocasio-Cortez (D-N.Y.) plan to introduce the joint resolution on Tuesday along with Rep. Earl Blumenauer (D-Ore.), adding momentum to a movement aimed at forcing governments to recognize the magnitude of the threat greenhouse gases pose.

“President Trump has routinely declared phony national emergencies to advance his deeply unpopular agenda, like selling Saudi Arabia bombs that Congress had blocked,” Keane Bhatt, a spokesman for Sanders, said in a statement.

“On the existential threat of climate change, Trump insists on calling it a hoax. Senator Sanders is proud to partner with his House colleagues to challenge this absurdity and have Congress declare what we all know: we are facing a climate emergency that requires a massive and immediate federal mobilization.”

The Guardian first reported the resolution on Monday.

It’s an entirely symbolic gesture, explicitly stating that “nothing in this concurrent resolution constitutes a declaration of a national emergency for purposes of ... any special or extraordinary power.”

The resolution officially acknowledges the risk of continued emissions and aggregates federal scientists’ forecasts of increased extreme weather and public health crises as the planet warms. It nods to the ways in which climate change exacerbates existing social inequities, such as racism and poverty.

Without naming it, the resolution makes the case for the sort of Green New Deal outlined in a February resolution all three lawmakers sponsored, touting the United States’ “proud history of collaborative, constructive, massive-scale federal mobilizations of resources and labor in order to solve great challenges, such as the Interstate Highway System, the Apollo 11 Moon landing, Reconstruction, the New Deal and World War II.”

On the off chance that Congress were to pass the resolution and President Donald Trump sign it, the United States would join 16 other countries and 740 local governments in declaring a climate emergency. Just last month, New York City became the largest city in the Americas to proclaim a climate emergency, following Hoboken, New Jersey, Oakland, California, and San Francisco.

The fact that there’s a resolution at all is a victory for advocacy groups like Climate Mobilization, which is tracking emergency declarations, and Extinction Rebellion, the activist group pushing governments to ramp up efforts to address the crisis.

But, generally speaking, there are reasons to be skeptical of declaring a national emergency on climate change. In February, climate researcher Alex Trembath argued in Slate that proclaiming climate change a national emergency threatens to give the federal government carte blanche to circumvent democracy in the name of mitigating the crisis. In The Outline, writer Casey Williams warned that such a declaration could open the door to untested, potentially disastrous geoengineering projects.

“Refusing a national emergency logic is not a call to ‘do nothing’; it is an insistence that climate change demands the resuscitation of democratic politics, not its suspension,” he wrote.