The Reliance Rail consortium denied it faced funding constraints and said it will deliver the first Waratah train into passenger service in December 2010.
The consortium will deliver new train carriages as part of the A$3.6bn (US$3.4bn) contract for the state-owned CityRail.
Currently, 12 Waratah trains are in various stages of manufacture, three of which are in final fit-out and assembly in Newcastle and the remaining set will be ready by October.
The fleet will replace 498 non-air conditioned train carriages and provide extra rolling stock capacity for the RailCorp network.
The consortium said it also completed the A$220m (US$210.9m) Auburn maintenance centre, simulator suite and static testing on the four-car Waratah prototype.
The Reliance Rail consortium includes Downer EDI, AMP Capital Investors while RBS is responsible for financing and maintaining the carriages under the project, according to AAP.