Nemak, a unit of Mexican conglomerate Alfa, said the Windsor plant represents 1% of its consolidated sales, employs 270 people and produces engine blocks.

"The decision comes on the back of the expected withdrawal from an export program by a client in China, which will lead the plant to use less than 10% of its installed capacity by 2020," the company said in a statement.

(Reporting by Rebekah F Ward; editing by Jonathan Oatis)