Vauxhall plans to cut a further 250 jobs at its Ellesmere Port factory, just months after saying it would slash 400 staff at the site.
The car manufacturer, which was bought by Peugeot-owner PSA Group in a £1.9 billion deal last year, said the move was designed to drive the "recovery of plant productivity".
As part of the job cuts, the Cheshire-based plant will move to a single production shift in April this year.
In a statement, Vauxhall said: "At a meeting held on Thursday 4 January 2018 between representatives from Vauxhall Motors and UNITE the Union, the company explained that although the initial voluntary separation programme at its Ellesmere Port plant announced in October (aligned to adjustment of production volumes in order to protect its future) has been successful, it needs to initiate a further voluntary programme for eligible employees of a further 250 heads in the period from April to the end of September 2018."
PSA, which owns Peugeot and Citroen, agreed to buy the loss-making European arm of General Motors (GM) in March.
The move aimed to secure GM's exit from the UK and Europe while transforming PSA into Europe's second-largest car maker.
However, the takeover sparked concern in the UK about the impact on thousands of jobs at Vauxhall plants and supply companies.