The Vauxhall and Opel brands are suffering from weaker sales
Carmaker Vauxhall is to cut 434 jobs across its two UK plants.
A total of 340 jobs are to go at its Ellesmere Port facility on Merseyside, and a further 94 at its van-making factory in Luton.
The lay-offs come days after parent company General Motors (GM) said it was to cut 12,000 jobs at its loss-making European division.
GM's European operations also include Opel, which this week has been hit by a strike at one of its sites in Germany.
A Vauxhall spokesman said the firm's losses in the UK had more than doubled from £51m ($92m) in 2002 to £115m last year, despite the success of the Astra car and the Vivaro van.
"Manufacturing wise we are in a strong position, but we are in a loss making business, and we need to work hard to address profitability," he said.
Dave Osborne, national officer of the Transport and General Workers Union, criticised the job cuts, saying workers had achieved good levels of efficiency over the past year.
Vauxhall workers will on Tuesday join a day of action across Europe, aimed at campaigning against plant closures or compulsory redundancies within General Motor's European operation.
But Detroit-based GM, the world's largest car manufacturer, is determined to cut costs at its European division by 500m euros ($623.8m; £347m) in an effort to reverse four years of losses.