Council workers in Birmingham have voted in favour of industrial action.
More than 90% of Amicus union members in the highway services department are affected by plans to transfer their jobs to a private company.
The action could hit road gritting, street lighting and traffic signal services in the city.
The union said it is hoping for a response from the council to avoid a strike.
Sign up to our weekly round-up of HR news and guidance
Receive the Personnel Today Direct e-newsletter every Wednesday
A statement from the council said: “The city council is still involved in amicable discussions with the unions about staffing arrangements under the proposed highways private finance initiative scheme, and strike action is not imminent.
A council spokesman added that they had not received seven days’ notice of strike action.