German car maker Opel, a unit of US giant General Motors, will reduce its production level next year and is mulling a 30-hour work week, directors told the Frankfurter Allgemeine Zeitung newspaper.

`We are getting set for tough times and revising lower by around 10 percent our (output) volume forecasts for 2009,` Hans Demant said in comments published on Tuesday.

Opel was to cut production of its Astra, Corsa and other models to 1.5 million vehicles from 1.7 million in an initial estimate. Demand has fallen in almost every global car market.

To avoid firing workers, `a 30-hour work week is being studied in all of our European factories,` said Klaus Franz, head of Opel`s works committee.

An exception would be made however for the the group`s biggest German plant in western Ruesselsheim, which makes its newest model, the Isignia.

It was selected as European car of the year, and the group is pinning its hopes on the car`s success.

Meanwhile, Opel has asked the German government to guarantee loans it might need if the US parent group goes bankrupt.

Chancellor Angela Merkel has said she will make a decision on the request before the end of December.

But on Tuesday, Demant told the newspaper that `even in the event of a deep recession, our future liquidity is assured without a guarantee.`