The city's inside workers voted 85 per cent in favour of a strike mandate Tuesday, their union says, setting the stage for a strike or lockout that could begin as early as early Saturday.

At a news conference Wednesday morning, CUPE Local 79 president Tim Maguire said members gave the union's bargaining team greater leverage in the final days of negotiations, although he repeatedly told reporters the union has no plans to walk off the job if collective agreements aren't in place by a weekend deadline.

However, Maguire said the union "would have to consider other actions" if the city strips workers of basic employment protections. He stopped short of saying the union would walk off the job in that scenario.

The union wouldn't say how many of its members cast ballots in Tuesday's vote, which was held as the city and CUPE Local 79, which represents 23,000 city workers, face a bargaining deadline of 12:01 a.m. on Saturday.

"We are prepared to keep bargaining beyond the arbitrary deadline imposed by the city," Maguire said in a news release issued early Wednesday when results of the vote were announced. "We are going to consider the option this mandate gives us if the employer starts to gut our collective agreement and strip away basic rights and protections."

According to the union, the city has threatened to impose "terms and conditions" of employment - including unilateral changes to wages, hours of work and benefits, and stripping worker protection against unfair discipline - if a deal isn't reached by the deadline.

If a strike or lockout occurs, many city buildings will likely be closed – including city-run daycares, community centres, museums and swimming pools – and many city services will likely be halted.

Services that would be affected include non-emergency public health programs, permits for parks, tennis courts and sports fields and the processing of building permits and rezoning applications.

About 2,300 Toronto Public Library workers went on strike earlier this week, meaning public libraries are closed until the labour dispute is resolved.

Library workers are walking picket lines outside city hall and at least six public libraries Wednesday.

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