Federal Industry Minister Greg Combet says he is confident he's done enough to secure the $1 billion needed from big business to fund the government's manufacturing rescue package, despite leaked documents suggesting otherwise.

The plan gives local firms first opportunity to bid for contracts, and creates new manufacturing precincts to help small and medium sized businesses develop new products and skills to break into new markets.

It will be funded by removing a tax concession for big business, which currently benefit from special research and development tax breaks.

But cabinet documents leaked to Fairfax Media show Mr Combet's department argued against the plan.

The advice warned it could be difficult to legislate to stop big companies avoiding the policy by restructuring and shifting earnings offshore.

Mr Combet said those risks had been reduced since the leaked document was written.

"I think that the document that has been leaked canvassed some options, some risks associated with them after that process was gone through," he said.

"Of course we went through and looked at how we would mitigate risks and overcome them."