Holden's temporary and casual workers could lose their jobs at the car maker's Elizabeth plant because the high Australian dollar has hit export growth, South Australian Premier Jay Weatherill says.
But the permanent workforce will not be hit by the job cuts, he says.
Workers are expected to be told this week how it will affect them.
The premier made his comments on Wednesday after news of the decision became public.
"It does indicate that the future security of Holden's will depend on us being able to ensure that Holden's invest in a new platform which will secure jobs into the future," the premier said in Adelaide.
Mr Weatherill said that platform would not be dependent to the same degree on fluctuations in the dollar.
Holden managing director Mike Devereux is in Adelaide to tell workers about operations and is expected to release details on Thursday.
Mr Weatherill did not say how many workers would be affected, only that casual and temporary jobs would be "scaled back" over the next few months owing to fewer than anticipated export sales.
There is uncertainty over the car maker's long-term manufacturing future in Australia.
Mr Weatherill said negotiations were taking place between Holden, the South Australian and federal governments on assistance measures.
He said the state government had been told in December that job losses were on the cards, and had argued against them.
"What this demonstrates is the seriousness of the current talks," he said.
Mr Weatherill said SA would do what it could to safeguard the 2000 jobs at Elizabeth and the total 8000 jobs in the industry.
Without change they were not secure, he said.
Mr Weatherill said Holden expected the job losses to come via natural attrition over several months.
The government would support the affected workers where possible, he said.
- AAP