Unifor has taken over the Nemak plant by setting up blockades at the entrances to the facility in protest of a planned closure. (Ricardo Veneza/CTV Windsor)

Unifor says it is disappointed in the Nemak arbitration decision.

Unifor national president Jerry Dias says he is shocked by the rationale the arbitrator gave for siding with Nemak's plant closure agreement and their intention to move the jobs to Mexico.

Dias says the ruling contains numerous errors and the union is considering pursuing a urgent judicial review.

He goes on to say of particular concern is the addition of conditions not in the collective agreement's language.

Unifor says the addition of conditions changes the collective agreement's terms, which is not permitted under its arbitration provisions.