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About 1,000 workers at Jaguar's Castle Bromwich plant in Birmingham will move from a five-day to a three-day week from October until Christmas.

Jaguar Land Rover said it was making "temporary adjustments to our production schedules" at the factory.

It was standard practice to "regularly review its production schedules to ensure market demand is balanced globally", JLR added.

It affects about half the plant's 2,000 workers, who will remain on full pay.

The move means production of Jaguar cars will slow - many of which have diesel engines. Diesel sales have sunk as buyers question their environmental impact.

Jack Dromey, the Labour MP for Erdington, blamed "Brexit chaos and the mishandling by ministers of the transition from diesel" for the three-day week.

He told the BBC the government had sent "the message that somehow if you buy a diesel car, they'll be worthless, in circumstances where actually the new generation diesels are ultra low emission produced by the company. So there's been a real problem there."

Despite the "continuing headwinds" affecting the car industry, JLR said it was committed to its UK plants, "in which we have invested more than £4bn since 2010 to future-proof manufacturing technologies to deliver new models".

As well as Castle Bromwich, JLR also has plants in Halewood and Solihull.

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Assistant general secretary of the Unite union, Tony Burke, pointed the blame at Theresa May.

"This is the continuing effect of the chaotic mismanagement of the Brexit negotiations by the government, which has created uncertainty across the UK's automotive industry and the manufacturing sector generally," he said.

Last week, JLR boss Ralf Speth warned the government to get "the right Brexit" or risk big job cuts at the carmaker and wiping out its profits.

The production cutbacks come on the day that Sir Bernard Jenkin, the Tory MP and Brexit supporter, accused Mr Speth of scaremongering with his predictions.

"I'm afraid I think he's making it up. We've had figures made up all the time by the scaremongers in this debate and I'm afraid nobody believes them," he told the BBC's Today programme.

Sir Bernard's comments were described as "embarrassing" by pro-Remain Tory backbencher Anna Soubry.

The company said in April it would not renew the contracts of 1,000 temporary workers at two factories.

JLR is owned by India's Tata Motors and employs 40,000 people directly, with another 260,000 working in its supply chain.

In July, Jaguar Land Rover warned that a "bad" Brexit deal would threaten £80bn worth of investment plans for the UK and could force it to close factories.

Last year, it made more than 600,000 cars, a fifth of which were sold to mainland Europe.