OMAHA, Neb. (AP) President Joe Biden on Monday called on Congress to pass legislation to intervene and block a railroad strike before next months deadline in the stalled contract talks.

Biden said a tentative agreement approved in September provided a pay raise for workers, health care benefits and a better leave policy.

But talks have since stalled. Four rail unions are back at the table after rejecting their deals with the railroads, trying to work out new agreements before the Dec. 9 deadline. Eight other rail unions have ratified their deals that include 24% raises and $5,000 in bonuses.

Labor leaders have asked Congress to step in. Lawmakers have the power to impose contract terms on the workers, but its not clear what they might include if they do that. They could also force the negotiations to continue into the new year.

Let me be clear: a rail shutdown would devastate our economy, Biden said in a statement. Without freight rail, many U.S. industries would shut down.

THIS IS A BREAKING NEWS UPDATE. APs earlier story follows below.

OMAHA, Neb. (AP) Business groups are increasing the pressure on lawmakers to intervene and block a railroad strike before next months deadline in the stalled contract talks.

A coalition of more than 400 business groups sent a letter to Congressional leaders Monday urging them to step into the stalled talks because of fears about the devastating potential impact of a strike that could force many businesses to shut down if they cant get the rail deliveries they need. Commuter railroads and Amtrak would also be affected in a strike because many of them use tracks owned by the freight railroads.

The business groups led by the U.S. Chamber of Commerce, National Association of Manufacturers and National Retail Federation said even a short-term strike would have a tremendous impact and the economic pain would start to be felt even before the Dec. 9 strike deadline because the railroads would stop hauling hazardous chemicals, fertilizers and perishable goods up to a week beforehand to keep those products from being stranded somewhere along the tracks.

A potential rail strike only adds to the headwinds facing the U.S. economy, the businesses wrote. A rail stoppage would immediately lead to supply shortages and higher prices. The cessation of Amtrak and commuter rail services would disrupt up to 7 million travelers a day. Many businesses would see their sales disrupted right in the middle of the critical holiday shopping season.

A similar group of businesses sent another letter to President Joe Biden last month urging him to play a more active role in resolving the contract dispute.

Congressional leaders and the White House have said they are monitoring the contract talks closely but havent indicated when they might act or what they will do. House Majority Leader Steny Hoyer, D-Md., said leaders are aware of the situation with the rail negotiations and will monitor the talks in the coming days.

Rep. Brian Fitzpatrick, R-Pa., said on Fox News Sunday that Congressional intervention is a last resort, but lawmakers will have to be ready to act.

Congress will not let this strike happen. Thats for sure, said Fitzpatrick who helps lead a bipartisan group of 58 lawmakers. It would be devastating to our economy. So, well get to a resolution one way or another.

A White House spokeswoman has said that a rail strike would be unacceptable.

Congress has the power to impose contract terms on the workers, but its not clear what they might include if they do that. They could also force the negotiations to continue into the new year.

Both the unions and railroads have been lobbying Congress while contract talks continue. Four rail unions that represent more than half of the 115,000 workers in the industry have rejected the deals that President Joe Biden helped broker before the original strike deadline in September and are back at the table trying to work out new agreements. Eight other unions have approved their five-year deals with the railroads and are in the process of getting back pay for their workers for the 24% raises that are retroactive to 2020.

It certainly could end up in Congress lap, which is why we are headed to D.C. this week to meet with lawmakers on The Hill from both parties, said Clark Ballew, a spokesman for the Brotherhood of Maintenance of Way Employes Division union that represents track maintenance workers. We have instructed our members to contact their federal lawmakers in the House and Senate for several weeks now.

The unions have asked the railroads to consider adding paid sick time to what they already offered to address some of workers quality of life concerns . But so far, the railroads, which include Union Pacific, BNSF, Norfolk Southern, CSX and Kansas City Southern, have refused to consider that.

The railroads want any deal to closely follow the recommendations a special board of arbitrators that Biden appointed made this summer that called for the 24% raises and $5,000 in bonuses but didnt resolve workers concerns about demanding schedules that make it hard to take a day off and other working conditions .