The potential for a Winnipeg Transit strike is rising as the union representing bus drivers and mechanics is poised to reject what the city describes as a final contract offer.

The City of Winnipeg and the Amalgamated Transit Union Local 1505 have been without a collective bargaining agreement since January.

The union, which represents about 1,400 Winnipeg Transit workers, voted on April 5 to reject a city contract offer by a margin of 98 per cent. Transit drivers also staged a job action on May 14, when they declined to enforce fare payment, a move that cost the city approximately $45,000 in lost revenue.

On May 17, the city presented the union what it described as a "final package offer" for a four-year contract that includes three annual wage increases of 1.75 per cent.

The city also sent copies of the contract directly to transit workers "so they are able to see the proposal unedited before they have to vote on it," Winnipeg communications director Felicia Wiltshire said in a statement.

"We offered wage increases over the course of a four-year contract that we felt were reasonable and were in line with agreements made with our other unions that we have negotiated with over the past couple of years," Wiltshire said.

"We also strived to offer employees a better work/life balance with the introduction of flexible spare operator positions, along with formalizing the shift switches and trades process."

The transit union's membership will vote on the contract this week, with a result expected on Friday.

Winnipeg Transit workers have been without a collective bargaining agreement since January. (Jeff Stapleton/CBC)

Aleem Chaudhary, president of ATU 1505, said he is recommending his members reject the contract because he claims the city failed to address a range of concerns, including the provision of sufficient time for drivers to relieve themselves or get out for their seats for a few minutes.

"We don't have time for our operators to go to the bathroom or recover down the line," he said in an interview. "No matter what, the operator [needs] five minutes of recovery time to get out of the seat, stretch his legs [and] walk around the bus a couple of times, just to have a little bit of mental relaxing time."

Chaudhary did not raise transit safety concerns as a sticking point. His union has spent two years lobbying for increased measures, such as placing police officers on buses.

The union president, however, chided the city for providing CBC News with a copy of its contract offer.

"To be honest, we expected better from the City of Winnipeg than to leak portions of the offer to media and the public. We call on the City of Winnipeg to follow the directive of Mayor [Brian] Bowman in not bargaining through the media, and it is unfortunate that there seems to be a disconnect between the civic administration and the mayor's office," Chaudhary said.

Future negotiations with the city will take place in a public venue because, he claimed, the city has acted in bad faith.

"We will be taking the step of inviting members of the public and our membership to attend negotiations with the city in public, in order to see firsthand how the city values its transit riders and workers," he said.

Winnipeg chief corporate services officer Michael Jack said he hopes the union accepts the offer but does not know whether a lockout is an option for the city. (Gary Solilak/CBC)

The results of the union vote should be known on Friday. A rejection will amount to a strike mandate, union spokesperson Zach Fleisher said.

Transit workers have not gone on strike since 1976. It's unclear whether the city is considering a lockout.

Winnipeg chief corporate services officer Michael Jack said he does not know whether the city would lock out transit workers. He said he hopes the union accepts its final offer so the city "can continue to provide transit service" to passengers who rely on it.

Bowman said Monday he is not contemplating a lockout if the union rejects the city's offer, adding transit service is too important. The mayor also said he's disappointed the union continues to talk about a strike.

Jack, however, noted a lockout remains one option the city could explore.