U.S. President Joe Biden on Monday called on Congress to intervene to avert a potential rail strike that could occur as early as Dec. 9, warning of a catastrophic economic impact if railroad service ground to a halt.

Biden asked lawmakers to adopt the tentative deal announced in September “without any modifications or delay – to avert a potentially crippling national rail shutdown” and added that up to 765,000 Americans “could be put out of work in the first two weeks alone.”

House Speaker Nancy Pelosi said lawmakers would take up legislation this week “to prevent a catastrophic nationwide rail strike, which would grind our economy to a halt.”

On Monday, more than 400 groups called on Congress to intervene in the railroad labor standoff that threatens to idle shipments of food and fuel and strand travelers while inflicting billions of dollars of economic damage.

A rail traffic stoppage could freeze almost 30% of U.S. cargo shipments by weight, stoke inflation and cost the American economy as much as $2 billion per day by unleashing a cascade of transport woes affecting U.S. energy, agriculture, manufacturing, healthcare and retail sectors.

“A rail shutdown would devastate our economy,” Biden said. “Without freight rail, many U.S. industries would shut down … Communities could lose access to chemicals necessary to ensure clean drinking water. Farms and ranches across the country could be unable to feed their livestock.”

Biden hailed the contract deal that includes a 24% compounded wage increase over a five-year period from 2020 through 2024 and five annual $1,000 lump-sum payments.

Labor Secretary Marty Walsh, Transportation Secretary Pete Buttigieg and Agriculture Secretary Tom Vilsack have been involved in discussions with the rail industry, unions and agriculture industry stakeholders.

Senator Roger Wicker, the top Republican on the Commerce Committee, praised Biden’s call to Congress to act and said no one side was fully happy with the compromise contract deal “but the responsible thing to do is avoid the strike.”