State Labor is set to draw a line in the sand over the controversial east-west tunnel, with Opposition Leader Daniel Andrews to announce he is unambiguously against the $6-$8 billion project, one of the largest in Victoria's history.

Senior ALP sources yesterday confirmed the Opposition's intention to support and new road linking the western suburbs to the Port of Melbourne, and for works to ease congestion along Hoddle Street.

Fairfax Media understands the shadow cabinet firmed its position at a meeting on Tuesday morning.

Labor is also committed to the $9 billion metro rail tunnel, which has been backed by Federal Labor.

Since the Coalition embraced the eastern link - from the Eastern freeway at Clifton Hill to Tullamarine freeway - as a priority in late 2011, Labor has struggled with the politics of the state's biggest infrastructure project.