President Joe Biden arrives back at the White House in Washington
U.S. President Joe Biden approaches reporters to answer a question about the crisis in Ukraine and the missile that crashed in Poland as he arrives back at the White House from travel to the G20 and ASEAN summits, on the South Lawn of the White House in Washington, U. Reuters

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 the potential dire economic impact.

Biden asked lawmakers to adopt the tentative deal announced in September "without any modifications or delay - to avert a potentially crippling national rail shutdown."

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 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."

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, White House Press Secretary Karine Jean-Pierre said.

In a letter sent on Monday, the U.S. Chamber of Commerce, National Association of Manufacturers, National Retail Federation, American Petroleum Institute, National Restaurant Association, American Trucking Associations and other groups warned that impacts of a potential strike could be felt as soon as Dec. 5.

Biden said Congress "should set aside politics and partisan division and deliver for the American people. Congress should get this bill to my desk well in advance of December 9th so we can avoid disruption."

Workers in eight unions have approved a tentative contract deal announced in September, while four rejected it.

"The risks to our nation's economy and communities simply make a national rail strike unacceptable," says the letter to congressional leaders first reported by Reuters. "Therefore, absent a voluntary agreement, we call on you to take immediate steps to prevent a national rail strike and the certain economic destruction that would follow."

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.

The letter warned a strike could halt passenger railroad Amtrak and commuter rail services that "would disrupt up to 7 million travelers a day."

Biden's Presidential Emergency Board in August released the framework for the tentative deal forged in September between major railroads and a dozen unions representing 115,000 workers. Those carriers include Union Pacific, Berkshire Hathaway Inc's BNSF, CSX, Norfolk Southern and Kansas City Southern.

Unions and railroads have until Dec. 9 to resolve differences. If they do not, workers could strike or railroads could lock out employees - unless Congress intervenes. But railroads would halt hazardous materials shipments at least four days ahead of a strike deadline.

The Washington Post first reported Biden's plans.