Car giant Nissan is to end the night shift at its Sunderland plant, workers have been told.
Unite said it believed no jobs will be lost as a result of the decision, but workers will lose a shift allowance.
The move follows a decline in car sales and has raised fears of a knock-on effect in firms that supply Nissan with parts.
The plant employs about 3,000 workers on the night shift.
Unite assistant general secretary Steve Turner said:
Unite has been aware of this announcement for some time and our officers and reps at the plant have been working hard to ensure that the full workforce is protected.
In a statement, Nissan said:
To support the production of new Juke, extra manufacturing staff will be needed on the plant’s production Line Two.