Three consortiums have lodged expressions of interest for the right to build and operate the 39-km Western Sydney Orbital tollway, the largest infrastructure project in Australia since the Snowy Mountains scheme.

The Roads and Traffic Authority has said a decision would soon be made on which bidders would be allowed to submit more detailed proposals.

Transport planners hope the road will boost the development of purpose-built industrial parks and hubs for public transport.

It is likely to have separate lanes exclusively for public transport and room for light and heavy rail.

The government has committed A$350 million ($184 million) to the $1.25 billion freeway, due to be completed by 2007.

The three consortiums are: