Australia’s iconic carmaker could be looking for more stimulus money from the Federal Government to stay afloat, reports say.

The company was promised a $275 million co-investment package last year, with $215 million to come from Federal coffers and the remaining $60 million from the South Australian and Victorian Governments. The boost was in exchange for Holden building two next-generation vehicles at their plant in Adelaide.

Australian Manufacturing Workers' Union SA secretary John Camillo would not reveal how much additional funding was being sought, but confirmed the co-investment was under review; "they are seeking more funds in regards to replacing the Cruze and the Commodore," he said. "They have made it quite clear that no matter what the workers do, if they do not get more support from the government they will not go forward with the Cruze and the Commodore."

There are 4000 fewer workers at the Adelaide factory from 2005 to now. Only 1700 people now man the machines and even they are being asked to accept pay cuts to keep the company alive.

Minister for Industry Kim Carr has said he has been in discussions with Holden about the company's future operations.

"We remain committed to supporting car manufacturing," Carr said. His office later refused to provide details on talks with Holden to finalise a funding contract.

Holden is refusing to reveal the amount of funding required to guarantee its Australian presence.