Carmakers Daimler AG (DAIGn.DE) and Porsche (PSHG_p.DE) plan short working hours at plants in Germany later this year, abandoning hopes that a year-long sales swoon could reverse quickly.

Despite record sales in China and a series of new models, Daimler intends to put staff on short hours again in the fourth quarter. A spokeswoman said on Thursday the company had applied for short hours at most German sites as a precautionary measure.

Around a quarter of Daimler's 160,000 staff in German car, truck and parts plants are already on short hours under a scheme in which the government helps subsidize pay for affected workers as a way to avoid layoffs.

Daimler's premium Mercedes Car Group saw global vehicle sales slump 17.5 percent in the first seven months of the year. Sales at its market-leading trucks business plunged 48 percent in the first half.

Porsche Automobil Holding SE said it would cut output at its main sports car plant near Stuttgart for 18 days by year end, building 2,500 fewer cars.

The head of the IG Metall labor union had said on Wednesday he expected carmakers such as Volkswagen AG (VOWG.DE) to use short hours in response to the end of the government's 2,500 euro ($3,571) subsidy for motorists who scrap old cars and buy new ones.

Volkswagen (VOWG.DE) said it had no plans to expand short hour schemes.

Mercedes's arch-rival BMW (BMWG.DE), the world's biggest premium car maker, said it would end short hours at one plant in September and October and plans for subsequent months were not yet set.

(Writing by Michael Shields; Editing by David Holmes)

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