BMW has announced it is shedding 850 jobs at its Cowley plant in Oxford and scrapping weekend shifts.
All agency workers who did the weekend shift have been made redundant with immediate effect, reports the BBC website.
The Oxford site is also closing for a week and will re-open on Monday, February 23.
BMW said all staff at the factory, including remaining agency workers, would be paid their basic wages during the closure.
Meanwhile, the carmaker said it had identified 150 surplus workers at its Mini plant in Swindon.
These employees will be offered a transfer to work in Oxford.
The shift pattern change and resulting job losses will take affect on March 2.
A BMW statement said: "Mini plant Oxford will be bringing in a new shift pattern in response to continuing volatile market conditions.
"As of Monday 2 March, the plant will go from a three-shift to a two-shift pattern, operating five days per week instead of the current seven."
A Mini spokesman confirmed at the weekend the company was in discussions with Unite union representatives over changes to shift patterns at the plant.
The spokesman said their first priority was to communicate with the workforce.
However Tony Woodley, Unite joint general secretary, said: "The manner in which these cuts were announced today was disgraceful.
"It is tough enough for workers in those car companies who have seen their market collapse in recent months, but BMW makes a top-selling product in the Mini and owed it to their staff to treat them better.
"Sacking an entire shift like this, and targeting agency workers who have no rights to redundancy pay, is blatant opportunism on BMW's part and nothing short of scandalous."
Woodley added Unite would be seeking to meet with the company as soon as possible to fight against the cuts which it felt was needless.
Unite will also be pressing the Government to do more to protect jobs in this country.