An underground rail line project in Brisbane that forms a major part of Queensland's A$5.4bn ($4.27bn) Cross River Rail development is set to be delivered under a private-public partnership (PPP).

The partnership will oversee the construction of four new underground stations, in addition to the completion of other related works along the 10.2km rail link, according to smh.com.au.

The project will also see the construction of a tunnel from Dutton Park station to the northern portal, as well as the integration of the rail systems with the planned tunnel section.

Additionally, the PPP is expected to collaborate with Queensland Rail to connect the Cross River Rail corridor with the existing network.

"Cross River Rail creates 1,500 jobs every year during construction and 3,000 in the peak, and we’re already seeing this project benefit local companies."

The government has announced that preliminary works related to the project have already begun, following the commencement of construction of the new Woolloongabba Station.

Queensland Deputy Premier Jackie Trad said: “Cross River Rail creates 1,500 jobs every year during construction and 3,000 in the peak, and we’re already seeing this project benefit local companies.

“Geotechnical investigations are also about to start along the Cross River Rail corridor.

“This project will ensure high frequency, turn up and go services for commuters, with the major beneficiaries being the outer regions like the Gold Coast, Sunshine Coast, Redlands and Ipswich.”

The Cross River Rail Delivery Authority is the body responsible for the project's development, and has conducted an industry briefing to demonstrate its procurement approach, governance, details of major work packages and delivery strategy.