About 2,200 jobs in Jaguar Land Rover manufacturing plants are at risk.
The Unite union has said that 40% of DHL Supply Chain staff in factories in the Midlands and North West could lose their jobs.
Unite said it was “a hard and bitter blow” and called on the government to protect the automakers as production fell due to the coronavirus.
DHL Supply Chain blamed “the very difficult business conditions” and said it would aim to redeploy staff.
At-risk agency workers are employed in JLR factories at Castle Bromwich, Ellesmere Port, Halewood, Hams Hall, Midpoint, Solihull and Tyrefort.
They work to deliver parts to warehouses and production lines and to transport completed vehicles.
Unite said the reductions were due to “efficiency savings” resulting from lower auto production.
Union logistics officer Matt Draper said he would not defend DHL “forcing workers to take on impossible workloads by showing the door to other workers”.
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More than 6,000 jobs in the UK auto sector were cut in June and one in six jobs is at risk.
The industry crashed in April, down 99.7% from the same month last year – the lowest production since World War II.
“Although DHL is the employer, the reality is that workers are doing their jobs for JLR,” said Draper, adding that JLR had “a moral duty” to support workers.
A JLR spokesperson said the company was “undergoing a transformation program in the context of the Covid-19 pandemic.”
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