(CNN) — In a rare move, more than 200 congressional staffers have sent a letter to Democratic leadership in the House and Senate, demanding they close the deal on a climate and clean energy package and warning that failure could doom younger generations.

“We’ve crafted the legislation necessary to avert climate catastrophe. It’s time for you to pass it,” the staffers wrote in a letter, sent to Senate Majority Leader Chuck Schumer and House Speaker Nancy Pelosi on Tuesday evening. The letter, which staffers signed anonymously with initials, was shared first with CNN.

“Our country is nearing the end of a two-year window that represents a once-in-a-generation opportunity to pass transformative climate policy,” the letter continues. “The silence on expansive climate justice policy on Capitol Hill this year has been deafening. We write to distance ourselves from your dangerous inaction.”

The staffers’ grievances were delivered as Schumer negotiates with Sen. Joe Manchin of West Virginia on a Democrat-only package that is expected to address inflation, the cost of prescription drugs, energy and the climate crisis. The climate and energy portion has remained the largest sticking point in negotiations, as Manchin has publicly stated he wants to lower gas prices by increasing US energy production.

“If you’re going to have gas prices lower, produce energy — period,” Manchin told reporters Tuesday as he left a Senate vote, reiterating he wanted a Democratic bill to lower inflation and the cost of gasoline and food.

But for Democratic congressional staffers — many of whom are young — passing massive investments in clean energy tax credits to deal with the climate crisis is especially urgent.

The effort to pen the staff letter started on Monday; by Tuesday, it had spread to many House and Senate offices, including offices in members’ home districts.

“It’s been very quick; this is extremely popular with congressional staff,” Saul Levin, a House Democratic staffer and coordinator of the Congressional Progressive Staff Association Climate Working Group, told CNN. “It’s taken no convincing, it’s like — ‘Where’s the link?'”

Levin said the letter was born of staffers’ frustration over the glacial pace of climate negotiations on the Hill, adding that many congressional staff have been working to craft big climate policy ideas well before Democrats had unified control of the White House and Congress.

“This rose up out of staffers’ frustration,” Levin said. “A lot of people have worked on this bill for years, since before Joe Biden was elected. [The letter] represents immense frustration of people who are really close to power and did our job. How can we go home and tell our families we did our job this whole time and there’s no climate policy?”

CNN has reached out to Pelosi’s and Schumer’s offices for comment.

The letter also discusses about young staffers’ fear of what will happen if Democrats don’t act to pass climate and clean energy measures. Human-caused climate change is already present in higher temperatures and more extreme storms, which scientists warn will only get worse if the earth continues to warm.

“If we are already witnessing the consequences of inaction in your lifetime, we can scarcely imagine what we will face in ours,” the letter states.

Anonymous letters from congressional staffers criticizing leadership are rare — especially ones that push for specific legislation — but staff have spoken out in letters before.

In summer 2020, Black staffers penned a letter to leadership urging action in the wake of George Floyd’s killing by a Minneapolis police officer. Over 400 staff members also signed a letter in December 2021 urging House leadership to condemn “incendiary rhetoric” in the workplace after Republican Rep. Lauren Boebert made anti-Muslim remarks against Democratic Rep. Ilhan Omar.

Still, the bulk of letters calling on congressional leadership to act on climate in the last year have come from outside climate advocacy groups.

Levin said the letter “demonstrates an age gap between staffers that are going to go through more of the climate crisis and Democratic leaders who aren’t.”

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