A railroad workers union on Monday rejected an agreement with the country's freight carriers, a move that could precede another strike. Railroad workers across the country had previously reached a deal with Class 1 freight railroads.

The Brotherhood of Maintenance of Way Employees Division voted against ratifying the proposed five-year contract in a 43-57% split, with the latter opposing the agreement. The vote brings the parties back to the negotiating table. In the event that discussions prove difficult, a strike could resume.

"The lack of paid sick time off was the most cited and specific concern of membership. It was especially evident during the pandemic that it was a major problem," a statement from the union said. "The railroads have so far not addressed it in any meaningful way."

Nearly 12,000 workers, over half of the 23,000 BMWE members, participated in the vote. The union is the third largest major freight railroad union.

Meanwhile, the two largest unions, which represent over 55,000 employees, are holding an independent rank-and-file ratification vote by mail.

Railroad workers agreed to a tentative deal on Sept. 15 after a 20-hour bargaining session, after President Joe Biden and Labor Secretary Marty Walsh stepped in.

The new contracts include a 14% raise with back pay dating to 2020, and raises totaling 24% during the five-year contract's life from 2020 through 2024. They also gives union members cash bonuses of $1,000 a year. However, workers remain opposed to scheduling and other work rules.

The major railroads carry 30% of the nation's freight when measured by weight and distance. The Biden administration has prioritized avoiding a rail shutdown considering the rocky economy as well the adverse impact of a prolonged strike.

President Biden touted the Sept. 15 agreement as "an important win for our economy and the American people" in a statement.

"These rail workers will get better pay, improved working conditions, and peace of mind about their health care costs: all hard-earned," he said.