Washington, Sep 16 (IANS): After a gruelling day of negotiations, US railroad firms and unions have reached a tentative deal, averting a potential rail strike that could be economically damaging.

US Secretary of Labor Marty Walsh took to social media to announce the agreement early on Thursday, writing that "following more than 20 consecutive hours of negotiations," the temporary deal "balances the needs of workers, businesses, and our nation's economy".

"The Biden administration applauds all parties for reaching this hard-fought, mutually beneficial deal," Walsh said.

"Our rail system is integral to our supply chain, and a disruption would have had catastrophic impacts on industries, travellers and families across the country," Walsh added.

The Association of American Railroads estimated in a recent report that a nationwide rail service interruption would idle more than 7,000 trains, and could cost more than $2 billion per day of a shutdown, Xinhua news agency reported.

The nation's two biggest rail unions reached the tentative deal after hours of negotiations, following nine other unions cut deals with the companies on Wednesday.

The Brotherhood of Locomotive Engineers Trainmen (BLET) and the SMART Transportation Division (SMART-TD), which comprise around half of all railroad employees, confirmed the tentative agreement in a statement on Thursday.

"Early this morning, following nearly three years of bargaining, the (BLET) and (SMART-TD) reached a Tentative National Agreement with the nation's largest freight rail carriers that includes wage increases, bonuses, with no increases to insurance copays and deductibles," the unions' in a statement said.

The deal also upgrades policies regarding time off for employees -- a major issue in the negotiations.

"For the first time, our unions were able to obtain negotiated contract language exempting time off for certain medical events from carrier attendance policies. Our unions will now begin the process of submitting the tentative agreement to a vote by the memberships of both unions," the union added.

In a statement on early Thursday, US President Joe Biden billed the agreement "an important win for our economy and the American people".

"These rail workers will get better pay, improved working conditions, and peace of mind around their healthcare costs: all hard-earned. The agreement is also a victory for railway companies who will be able to retain and recruit more workers for an industry that will continue to be part of the backbone of the American economy for decades to come," Biden said.