Italian construction and civil engineering company Salini Impregilo has been shortlisted for the A$2.2 – $2.4bn ($1.6bn) Sydney Gateway Project in Australia.

Part of an effort to improve infrastructure in the state, the bidding process is being handled by Transport for New South Wales (NSW).

As part of the project, road connections will be improved from Sydney Airport and Port Botany to the new Sydney motorway network at St Peters Interchange.

It is expected to provide substantial additional capacity in and out of the Sydney Airport and Port Botany precinct.

This will allow airport and port traffic to avoid local arterial roads while accessing WestConnex and the broader Sydney Motorway network.

The project will also involve the completion of missing links in the motorway network, enabling around 80,000 vehicles a day to travel on new roads.

The project will include a new flyover to the domestic terminals at Sydney Airport.

Last September, the Government of NSW approved the motorway project to reduce travel time to Sydney Airport and minimise the number of trucks on local roads.

The toll-free motorway will run from the WestConnex interchange at St Peters to Sydney Airport and closer to Port Botany.

It will also involve the duplication of a 3km stretch of freight rail line between Port Botany and Mascot.

In Sydney, Salini Impregilo has contributed to the construction of the Sydney Metro Northwest, the skytrain bridge and viaduct.