Congress and the Biden administration have blocked the possibility of a freight railroad strike.

Not quite a month after a national rail strike was averted, the possibility of a walkout has been resurrected.

Railroads and 12 labor unions had reached tentative contracts, but now one union has voted against ratifying its agreement.

On Monday, the Brotherhood of Maintenance of Way Employes Division of the International Brotherhood of Teamsters voted down the contract, sending the two sides back to the bargaining table and resetting the countdown for a potential work stoppage.

“Railroaders are discouraged and upset with working conditions and compensation and hold their employer in low regard. Railroaders do not feel valued,” Tony D. Cardwell, the union’s president, said in a statement.

“They resent the fact that management holds no regard for their quality of life, illustrated by their stubborn reluctance to provide a higher quantity of paid time off, especially for sickness,” he said.

“The result of this vote indicates that there is a lot of work to do to establish goodwill and improve the morale that has been broken by the railroads’ executives and Wall Street hedge fund managers,” he said.

Members of the union voted 6,460-5,100 against ratification, with 99 ballots submitted blank or voided for user error. The American Arbitration Association counted and verified the election results.

“The membership voted in record numbers on this tentative agreement, exhibiting that they are paying close attention and are engaged in the process,” Cardwell said.

“BMWED members are concerned with the direction of their employers and the mismanagement and greed in which they have consistently implemented and are united in their resolve to improve their working conditions across the entire Class I rail network,” he said.

The rejection of the tentative agreement results in a “status quo” period during which the union will restart bargaining with the Class I freight carriers.

That status quo period will extend to five days after Congress reconvenes, which is currently set for Nov. 14.

The National Carriers’ Conference Committee, which represents the nation’s freight railroads in national collective bargaining, issued a statement saying it is disappointed the union declined to ratify the tentative agreement.

The agreement implemented the recommendations of the emergency board appointed by President Biden, including a 24% compounded wage increase and $5,000 in lump sum payments, the committee said in the statement.

It also included significant increases to the national rules relating to reimbursements for travel and away-from-home expenses for the roughly 50% of the union’s members employed in traveling roles.

Four labor unions have ratified the tentative agreement, and ratification is pending with seven others.