Seattle on Monday became the first city in the nation to allow drivers of ride-hailing companies such as Uber and Lyft to unionize over pay and working conditions.

The City Council voted 8-0 in favor of the legislation, which is seen as a test case for the changing 21st century workforce. The companies strongly oppose it and are expected to challenge it in court.

Saad Melouchi, who drives for Uber, burst into cheers and hugged others outside City Council chambers after the vote. He says he wants to bargain over issues such as safety and wages.

Although Seattle has been a national leader on workers' rights, such as gradually raising the minimum wage to $15 and requiring most employers to provide paid sick leave, Mayor Ed Murray said that while he supports "the right of workers to organize to create a fair and just workplace" he would not sign the ordinance which, under the City Charter, will become law without his signature.

He added that he was concerned about "the relatively unknown costs of administering the collective bargaining process and the burden of significant rulemaking the Council has placed on City staff."

The ordinance allows drivers who take at least 150 trips within a 30-day period to collectively choose an “exclusive driver representative” to negotiate on their behalf with app-based, yellow cab and vehicle-for-hire companies and the city. The measure would not convert drivers into employees except for this limited purpose — a strategy originally developed by unions representing home health aides and child-care providers.

In most of the United States, taxi and Uber drivers are presumptively classified as independent contractors exempt from the minimum wage, workers’ compensation and the right to form a union. Yet this issue is being litigated fiercely, with some drivers alleging that companies like Uber and Lyft are in fact employers that exercise a high degree of control over their workers.

The text of the Seattle bill says that many businesses “rely on the drivers being classified as independent contractors” instead of employees, a practice that undermines city "efforts to create opportunities for all workers in Seattle to earn a living wage."

Al Jazeera and wire services