Council head Klaus Franz told German press agency dpa that, because gas guzzling cars were no longer in demand in the US, and the planned new truck architecture had been cut, there was a battle to divide up the work left.
GM Europe head Carl-Peter Forster told Spiegel that, even if the cars themselves were developed in the US, some of their parts could still be designed in Rüsselsheim.
The Rüsselsheim centre employs around 8,000 people and, from 2010, will develop all new GM models on a new small and medium car platform so there should be no immediate concern for the jobs there.
Opel is currently suffering from low sales volumes. Many European plants have been shutdown for a few days to adjust inventories. The Rüsselsheim plant has not been affected.