Unifor, which represents the 900 workers, has set a strike deadline of 2 p.m. ET.
National president Jerry Dias hopes the pending strike deadline will spark some progress today, but says the two sides were "stuck in the mud" over the weekend.
Dias says Bombardier wants to make changes to pensions and benefits that are unacceptable to the employees and are similar to demands that caused a brief strike in 2011.
He says the company walked away from the table on Saturday and conversations the two sides subsequently had on Sunday produced nothing of significance.
A Bombardier spokesman says the company is putting all its energy into reaching a deal that will ensure it remains competitive.
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