A road safety group says it is imperative budget wrangles do not put at risk any plans to buy new speed cameras.
Documents show the Treasury want any new speed cameras to be funded from the main police budget and not the road policing budget.
But police say that is not viable as it is unlikely new capital projects would be approved.
The documents say buying about 25 speed cameras for almost $4 million is vital for the national road safety strategy.
Mary Williams from the road safety charity, Brake, says there should be a dedicated budget for road safety tools.
Ms Williams says funding for the cameras could be easily sourced from fines generated by the cameras.