By Tapan Sharma

FRANKFURT--General Motors Co.'s (GM) loss-making European unit Adam Opel GmbH said Thursday it will introduce reduced working hours over 20 days through the end of the year at the Ruesselsheim and Kaiserslautern sites due to a slowdown in the European car market.

The company said it will switch to short-time work because of a "dramatic" drop in the European car market. Both production and administration at Opel will be affected by this step.

Opel employs around 16,000 people at the two facilities.

Short-time work is a German program designed to avoid job cuts, under which the state compensates employees for unworked hours. Opel said short-time work will be carried out for 20 days in the September-December period.

Write to Tapan Sharma at tapan.sharma@dowjones.com

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