Unifor is fighting to keep the Nemak plant open in Windsor.
The Mexican-owned aluminum casting company announced last month that it would end its Windsor operation by the middle of 2020, throwing about 270 people out of work.
"It's heartbreaking we all work hard every day to bring food home to our families," said Sherri Pukay, who has been working at the Windsor plant for four years. "To feel like we are getting back stabbed the way we are, it's very heartbreaking."
Unifor local 200 held a membership meeting on Sunday where officials told about 100 employees in attendance that they will fight the closure.
"We need our community to stay together to fight like hell to keep these products in our city and because I'm tired of seeing jobs go south," said John D'Agnolo, the president of Unifor Local 200.
The plant has been manufacturing engine blocks for General Motors China operations.
But the company announced its Chinese client decided to phase out of a contract early, meaning 90 per cent of the work at the Windsor plant is no longer needed.
CTV News learned the program was with GM Shanghai and sales of the vehicles that use a 2L engine block made at Nemak have dropped 75 per cent in China.
Unifor argues Nemak is also backing out of its contract with workers early, since they have a deal until 2022.
Since 2015, Nemak has received $4.5 million from the federal and provincial governments to support its Windsor production. But D'Agnolo said Windsor can't compete with wages in Mexico.
"Unfortunately they have a red carpet in place to go to Mexico and we can't do a damn thing about it because we don't have anything in place, policies in place to protect those jobs in our community," said D'Agnolo.
A number of local politicians also attended Sunday's meeting including Windsor Mayor Drew Dilkens.
He is holding out hope that the plant can stay open.
"They're not selling the plant yet, so that gives me some glimmer of hope that there's the prospect that business comes back," said Dilkens.
Unifor has now requested a meeting with the CEO of Nemak.
Unifor national president Jerry Dias says he is willing to meet anywhere in the world.
Union officials hope to have details about a meeting on Tuesday, and they hope to have more answers in the coming weeks so workers can plan for the future.