Most New York City Council members remain largely undecided about a possible ban of the horse-drawn carriages of Central Park.

While New York City Mayor Bill de Blasio is pushing ahead with his campaign promise to ban the carriages, the move also pits him against the labor unions that helped propel him to office.

The issue is a highly contested one. The mayor has supporters in animal-rights groups on one side, and on the other are the city’s unions, which have expressed concerns about job losses if the horses are banned.

About 350 workers are employed by the carriage industry, which is represented by the Teamsters Local 553.