A bipartisan coalition of California business leaders said Tuesday that hundreds of thousands of jobs and billions of dollars are at stake if Congress fails to pass legislation salvaging DACA, the program that has let hundreds of thousands of young undocumented immigrants stay in the U.S.

President Donald Trump on Sept. 5 announced he was phasing out the Deferred Action for Childhood Arrivals program in the next six months, giving Congress a last-ditch opportunity to step in during that time. Amid rumblings in Washington about a possible government shutdown over the DACA impasse, the business leaders urged Congress to act by the end of the year.

“Uncertainty is hard on both the employee and the employer,” said Gary Toebben, president and CEO of the Los Angeles Area Chamber of Commerce. “We dread the thought of more ICE raids relative to those DACA recipients.”

DACA granted deportation relief and temporary work permits to young undocumented immigrants who were brought to the U.S. as children. Of the nearly 800,000 DACA recipients across the country, an overwhelming amount — about 230,000 — live in California.

The business leaders who urged Congress to act Tuesday are members of the Regional Economic Association Leaders (R.E.A.L.) Coalition of California. The association represents 20 member organizations and up to 15,000 employers who collectively provide up to 3.9 million California jobs.

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The business leaders emphasized that ending the Deferred Action for Childhood Arrivals program would cause businesses to lose bright, dedicated employees who only know the United States as their home, which would ultimately result in a significant financial loss. The young migrants are often known as “Dreamers” after past legislative efforts to give them a path toward citizenship.

Carl Guardino, president of the Silicon Valley Leadership Group, said that loss would be particularly damaging in Silicon Valley, where immigrants are an integral part of the region’s tech world.

“We don’t want to see our Dreamers left on the side of the road because of an inaction from Congress,” he said.

About 57 out of every 100 jobs in Silicon Valley requiring a bachelor’s degree or higher are filled by someone who wasn’t born in the U.S., according to Guardino.

Trump has said he’d be willing to revisit the issue if Congress doesn’t act.

Organizations such as the Federation for American Immigration Reform in Washington, D.C., applauded the administration’s decision to rescind DACA, arguing the program was “an unconstitutional abuse of executive authority.”

“Congress should seize this opportunity to come together and forge these much-needed reforms in our nation’s immigration policy,” said FAIR President Dan Stein in a statement. “If the Democrats fail to show up at the negotiating table, it raises the legitimate question of whether DACA is something that the Democrats really want, or if it has merely been used as a convenient political football for fundraising and energizing their base.”

Members of the coalition hail from across the political spectrum: Toebben and San Diego Regional Chamber of Commerce President Jerry Sanders are Republicans, like the president and the majorities in Congress. Guardino and Alicia Berhow, vice president of the Orange County Business Council, are Democrats.

The group last week sent a letter to House Speaker Paul Ryan and House Minority Leader Nancy Pelosi, urging them to pass Dreamer legislation.

“Absent a solution, California will experience the biggest economic setback of any state in the

nation, with an estimated loss of $11.6 billion in GDP,” the letter said.

“We have already invested in these young people by educating them in our schools, and they are now a vital part of our workforce, contributing to our economic growth and our society — as teachers, engineers, nurses and small-business owners. It makes no sense to squander these young people’s talents and penalize our own nation.”

Politicians in recent weeks have become increasingly worried that the debate over the fate of DACA and the Dreamers will lead to a government shutdown next month, according to a Politico report. Many liberal Democrats have threatened to withhold their vote to fund the government past the Dec. 8 deadline until Congress passes legislation for Dreamers. Meanwhile, some Republicans want congress to delay any decision until next year in order to gain leverage.