Philadelphia's largest municipal employee union, District Council 33, has voted to authorize a strike against the city.

Philadelphia’s largest union representing city workers officially authorized its members to go on strike if their demands for better wages are not met.

By almost a 7-1 margin, members of AFSCME District Council 33 have officially authorized leadership to call a strike when they feel it’s necessary if the city is unable to offer a contract the union will agree to.

AFSCME District Council 33 is the largest union representing Philadelphia employees, covering over 9,000 members including sanitation workers. The union is looking for a long-term deal that includes salary increases while the city is looking for a 1-year contract extension.

PHILADELPHIA (WPVI) -- Philadelphia's largest city workers union has wrapped up a strike authorization vote. However, ballots with the strike authorization voting will be counted on Thursday. District 33 represents at least 9,000 mostly blue-collar employees, including sanitation workers.

Bus, trolley, and transit operators in the city are currently working without a contract. The last contract expired at midnight on Thursday, but union workers held off on a strike as both sides decided to continue negotiations. Meanwhile, on Friday, the union representing suburban transit workers formally voted to authorize a work stoppage.

The union that represents thousands of Philadelphia mass transit system workers has agreed to delay a potential strike, saying progress was being made in ongoing contract talks.